East Bay ADU Tour 2023 - Project Profiles
This is a list of every project on the ADU Tour. We’ll add detailed surveys filled out by the homeowners, builders and designers for each project.
Here is a Google Map with all 17 locations.
Here is a downloadable PDF with some of the key stats for each project.
Quick links to the ADU project profiles
4 - Roosevelt Avenue, Berkeley
5 - Shattuck Avenue, Berkeley (trailer micro-)
6 - Derby, Berkeley
11 - Chabot Rd, Oakland
13 - Montgomery Street, Oakland
14 - Fairview Avenue, Piedmont
15 - Winsor Ave (under construction)
16 - e 36th St., Oakland
17 - 11th Ave, Oakland
October 21, 2023
10am - 3pm Self-guided ADU Tour
2:30pm 5pm ADU Tour Hub
Best routes - Pro Tips!
Please do NOT visit the ADUs starting at #1 or #17, or you will likely be stuck in a large wave of others trying to do the same thing. If you go in numerical order, start anywhere other than ADU #1 or ADU #17.
The tiny ADUs are also very likely to have lines at the beginning of the day (#1, #5, #6, #7, #11, #12).
Tickets and wristbands
You can get wristbands at any ADU.
You can show your order confirmation email (on phone or printed), or your ADU Academy badge (if applicable), or present a valid ID for the person who bought the tickets.
You’ll get a wristband for each ticket and be off to the races.
We will not be equipped to process orders on site the day of so please buy tickets for your friends and colleagues now: https://adu-tour.eventbrite.com/
Weather
We’ve got a nice partial cloudy forecast for Saturday. You know how it can change on a dime though so I’d recommend layers if it gets cool and a brimmed hat if the sun comes out to say ‘HI!’
I always bring a water bottle on tour day too!
The Hammerling Wines Hub
Starting at 2:30, we're going to be at Hammerling, with Prefab Models, a Demo Build, ADU Professionals, Networking and Food & Wine for purchase.
After a long day visiting ADUs, this is a great place to regroup and chat with people about what you saw.
It’s going to sound cheesy, but one of the best things you can get out of this day is an ADU buddy in your own city (who is hopefully a little bit ahead of you!)
So it’s worth the time to come and make friends.
Find us at the outdoor patio at Hammerling Wines in Berkeley from 2:30-5pm on Saturday. 1350 Fifth St, Berkeley, CA 94710
ADU #1
Carlson Blvd, Richmond
Design/Permits: Studio Shed www.studio-shed.com
Builder: Kenton Rogers, Jigsaw Construction 408-592-2061
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We wanted to have a place to live while we remodel our main home. After that we will rent it to family or friends. We are also thinking about aging in place and that the ADU might be housing for a caretaker someday.
What did you do to prepare for the ADU development process?
We started with the idea of getting a prefab ADU. We felt this would speed up the design and construction process. We also felt this would be less expensive than a custom ADU. We researched various prefab companies to find the one that best suited our needs. They recommended a contractor; we liked him and proceeded. We had a sense of how much it would cost after that research and have been able to pay for it from savings and earnings.
How are you using the ADU now, or how will you be using ADU once it's complete?
It is currently our kitchen as we work on building the storage built-ins and await our occupancy permit. In the near future we will live in it during the remodel of our home. After that we will rent it to a family member or friend most likely. Long term we may choose to rent the main house and use the ADU as a home base when we aren't traveling.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
This is a free standing, new construction studio apartment. It is 18x22 feet made from factory built panels that were brought to our house and assembled. It has a shed roof facing south for solar and letting in lots of light from the north side.
What's the total interior square footage?
396 sq ft
If it is attached to additional square footage, how much additional square footage, and what is that space used for?
What kind of heating system did you use?
Ductless minisplit
What month and year did you start the design work?
July 2022
What month and year did you submit the plans to the City?
November 2022
What month and year did you start construction?
March 2023
What month and year did you (or will you) get your Certificate of Occupancy?
October 2023
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No, that part was pretty straight forward.
What was the total cost of the project?
For this response, please include design, build, permit fees, adjustment fees, demo, sewer work, water line upgrades, electrical upgrades, all nishes. Then, please add in your estimated worth of your own labor. Err on the side of including everything for this response. This should NOT include landscaping or furniture. We will provide a single bottom-line cost for each project.
We estimate $270-290 thousand.
We chose a raised foundation to bring the ADU up to the floor level of main house. We intend to have a deck that joins the two buildings, adding about $10,000. We had a lot of expenses that were not related to the actual building of the ADU, but necessary to use it like upgrading the electrical service, replacing the sewer lateral and tying into it, bringing services to the ADU (electricity, communications, water, solar).
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
We have done a lot of work shepherding the project through the process of design, permitting, and construction. We have read the applicable codes in order to fully understand this process and has been instrumental in working closely with our contractor to keeping the project moving and heading off potential problems.
We have sourced, bought, and are building all the storage built-ins aside from the kitchen and bathroom. We will have a wall of storage, under bed storage, and storage under the banquette seating. We have also sourced extra kitchen cabinets and built-in appliances which were installed by the contractor.
Estimated sweat equity: $15,00-20,000
How do you think about the 'return on your investment' for this ADU?
In the short term it will mean we don't have to rent while our house is remodeled and decrease stress caused by delays and issues with a rental contract elapsing before the house is ready. We will also have the reassurance that the main house in secure during the time it is being remodeled since we will still be living on site.
In the long term we can rent it for $2000-2500 per month. Not counting the cost of a rental during remodeling, this means we could make that back in 10-12 years of renting. Intangible value is giving us the flexibility to rent to family members who may need a bit of support in order to launch, the flexibility to use it for a caretaker if we become infirm in the future, or as a home base for us as traveling retirees.
It certainly increases our property value either as a larger house if one family uses both buildings or as a house with built-in rental income..
Besides its small size, what green features did you include in your design?
We are under contract to filled our shed roof (south facing) with solar panels; enough to provide almost all of the electricity for the ADU and the main house including charging our electric cars. We have R21 insulation in the walls and R30 in the floor and roof.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Include anything above $2K that was out of the ordinary, if there was anything notable. Many of the ADUs won't have anything notable. Things that would be notable would be upgraded water service ($6K), tearing down old garage and foundation ($3K), separating shared party sewer ($10K), land use adjustment ($3K)
We chose to have the ADU placed on a raised foundation in order for it to be at the same level as the main house. Eventually there will be a deck on the main house that connects to the ADU's deck making it easy and accessible to move from one space to the other. This is part of our aging in place strategy. Also making the deck larger to create an outdoor kitchen and eating area. We expect this to make the small ADU live larger while allowing us to do things we love like grilling and enjoying the back yard.
What would you do differently, if you were to start over?
We would choose different windows that infringe less on the walkways and deck just outside the ADU. We would also choose to include the full deck size from the beginning. Getting a revised deck approved has been very difficult and time consuming.
What design aspect of your ADU are you (or will you be) most happy with?
We love that the kitchen is large enough to accommodate two foodies who like to cook.
The open space is well lit by the high transom windows making the space feel bigger than it is. For 400sf, the ADU feels open and spacious.
What design aspect of your ADU are you (or will you be) least happy with?
Because we don't have a lot of space between the main house and the ADU, we may regret having only awning and casement windows. All but the bathroom window are either along the walkway to the ADU or along the deck side of the ADU and stick out into spaces were people will frequently be passing or sitting.
What is element of your ADU, or the development process and outcome, that you are most proud of?
All of the clever storage ideas (storage under the bed and built-in seating) and the adjustable height workbench (meant for a home workshop) that doubles as a prep counter for cooking and a dining table.
What was the most surprising thing your learned during your design/build process?
We were surprised by how hard it was to get tradespeople (electrician, plumber, solar) on board. We were only able to get good tradespeople through our contractor.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Get a good contractor. Hands down this is the most important thing. A good contractor will steer you in the right direction, tell you when an added expense really does and does not make a difference, and connect you with good sub-contrators. A good contractor knows how to keep the project moving, is responsive, and helps you get the end product you want. Be involved, even an excellent contractor can't give you what you want unless you are involved in the process. Learn as much as you can about the process. Read the code, learn about the steps required to design and build your ADU. Even if you have a great contractor, there will be things that aren't caught. If something seems out of place, speak up. We have caught a number of things that could have delayed the project or given us a product we didn't like as well. Know if your city is favorable towards ADUs. We feel that Richmond has been helpful as they are in favor of ADUs, but some cities are not and may make the process more difficult. You can be another set of eyes on the process. Informed decisions are better decisions.
ADU #2
5638 Columbia Ave, Richmond
Design/Permits: Hector Orozco (civil engineer)
Builder: (Owner-Builder GC) Tony Acosta, BHBuilders.net
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We built our ADU in order to have a comfortable space for friends and family to stay in, and for the possibility of added income potential later down the road. We also wanted to create a space that was conducive to multi-generational living. Our original home is quite small, and the lot was a good size for building. We chose to build an ADU instead of expanding the square footage of the main house.
What did you do to prepare for the ADU development process?
Since Tony is a General Contractor, we already had professional relationships with all of the people we needed for the project. We first designed the rest of the backyard hardscape, making sure to envision how the ADU would fit in with the use of the yard. The entire project was our own design.
How are you using the ADU now, or how will you be using ADU once it's complete?
We are currently living in the ADU as we prepare to gut the main house and give it a complete make over.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
Ground up new construction
What's the total interior square footage?
600 sq ft
Editorial note from tour organizer: this unit has about 300 additional sq ft of loft/mezzanine space that does not have the headroom to be counted as habitable square footage. Built during the time there was a 16 foot height max, this is a very clever space that safely creates a bit of extra room in the unit!
What kind of heating system did you use?
minisplit; radiant heating
What month and year did you start the design work?
08/2020
What month and year did you submit the plans to the City?
01/2021
What month and year did you start construction?
6/2021
What month and year did you (or will you) get your Certificate of Occupancy?
1/2022
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No
What was the total cost of the project?
$420,000 all-in
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
$80K for GC services
How do you think about the 'return on your investment' for this ADU?
We now have the space we need to work from home and live comfortably
Besides its small size, what green features did you include in your design?
R-23 in the walls; R-38 in the ceiling; 2" foam insulation under the slab; everything is electric
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Exterior finishes (Ipe siding and stucco); high-end doors and windows; Glass railing in mezzanine; high-end appliances
What would you do differently, if you were to start over?
Value engineering
What design aspect of your ADU are you (or will you be) most happy with?
High ceilings and floating staircase
What design aspect of your ADU are you (or will you be) least happy with?
ceiling height in the mezzanine
What is element of your ADU, or the development process and outcome, that you are most proud of?
How well it integrates with the outdoor space
What was the most surprising thing your learned during your design/build process?
Cost of materials was constantly surprising since it was during the pandemic
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Get your budget straight, and order windows/doors well in advance; beware PG&E issues! Apply for your new electrical meter as soon as possible.
ADU #3
1108-A Masonic Avenue , Albany
Architect: Mercedes Corbell, Saha Studios
Builder: Amber Stitt
Why did you build an ADU? What different ways do you plan to use the ADU over time?
My husband was a collector and we decided that we would build a cottage on our property for me to live in so I would have my own space.
What did you do to prepare for the ADU development process?
We started by contacting Mercedes who we knew, We looked at several cottages she had been involved with and talked to two contractors with whom she had worked.
How are you using the ADU now, or how will you be using ADU once it's complete?
I am now living in the cottage. My husband died very suddenly so I am in the process of clearing out and doing some essential repairs on the family home.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
The cottage is newly constructed detached on our property.
What's the total interior square footage?
600 sq ft
If it is attached to additional square footage, how much additional square footage, and what is that space used for?
What kind of heating system did you use?
Ductless minisplit
What month and year did you start the design work?
May, 2020
What month and year did you submit the plans to the City?
June, 2020 ish
What month and year did you start construction?
June, 2020 ish
What month and year did you (or will you) get your Certificate of Occupancy?
June, 2021
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
Some additional work for the sewer/drainage system was required by the City
What was the total cost of the project?
$482,000 plus $90,000 design fee; Total $572,000
Editorial note from the tour organizer: The homeowner employed family members and is undergoing a lot of exterior landscaping work as well as work on the main house
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
We did no physical work other than picking out appliances, tile, flooring, paint, etc
How do you think about the 'return on your investment' for this ADU?
I have no monetary return on the investment as I live in the cottage while repairs, etc. are being done on the main residence. I know there will be a monetary return in the future.
Besides its small size, what green features did you include in your design?
All features are built to code and meet the Energy Performance Score required by the City of Albany.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
An old structure had to be torn down and the structure was built from the foundation up. There were some additional costs required by the East Bay Municipal Utility District.
What would you do differently, if you were to start over?
I am very satisfied with the resulting ADU.
What design aspect of your ADU are you (or will you be) most happy with?
The south facing Windows, high ceilings, design layout and room to entertain small groups
What design aspect of your ADU are you (or will you be) least happy with?
There have been some extra drainage problems due to unique property layout that have been taken care of. This was made worse by the increased rain the past two years.
What is element of your ADU, or the development process and outcome, that you are most proud of?
I love the design, cabinets, bathroom tile and extra cabinets, good lighting and over-all comfort.
What was the most surprising thing your learned during your design/build process?
I have always lived in pre-owned dwellings and didn't realize all the details required to build and equip a new dwelling. It was an amazing experience and, though a little overwhelming, is one I'm glad I've had.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
We had a couple of trees that we wanted to protect against damage from the construction and had an arborist advise us as to the best way to do this. The trees are still thriving.
ADU #4
2215 Roosevelt Avenue, Berkeley
Architecture: Ron Bogley Architect
Builder: Green Living Builders
Why did you build an ADU? What different ways do you plan to use the ADU over time?
Increase housing stock in Berkeley, decided to move in to it ourselves and rent out main house instead.
What did you do to prepare for the ADU development process?
Oh boy. Talked about it for a long time. Then interviewed architects, looked for contractor and decided what parts of the build I wanted to do myself.
How are you using the ADU now, or how will you be using ADU once it's complete?
Moving into it.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New construction. Detached.
What's the total interior square footage?
1000 sq ft
What kind of heating system did you use?
Mini splits
What month and year did you start the design work?
January 2020
What month and year did you submit the plans to the City?
September 2020
What month and year did you start construction?
September 2020
What month and year did you (or will you) get your Certificate of Occupancy?
Pending.
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
We had half built when local zoning change allowed us to build up to 20 feet high. So we had second story designed and added additional square feet. Now feels like a small house, not an ADU or tiny home. Hard to fit in stairs when you hadn’t planned on them in first design, and first floor was already built, along with half the roof.
What was the total cost of the project?
$800,000.00
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
$200,000 at least in sweat equity. I did all electrical, installed windows, painted interior/exterior, did flooring and tiling, assembled and installed cabinets, built shelving, and additional kickboard drawers, did all finish plumbing, installed toilet and urinal, built banquet and banquet storage, trim work.
How do you think about the 'return on your investment' for this ADU?
Renting main house will pay back ADU investment in 9.5-10 years. It has easily increased property value by $700,000 currently.
Besides its small size, what green features did you include in your design?
Closed cell insulation in ceiling, heat pump water heater, and HVAC, energy efficient windows, solar power, car charger for electric vehicles.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Engineering costs when redesigning for second story appx. $5000.
What would you do differently, if you were to start over?
As much planning on the design as possible to reduce costs for changes in construction stage. I would have probably done more off the shelf window sizes and would know cabinet sizes and do full layout before designing the kitchen. Every detail not well thought out that requires some type of building change equals more cost.
What design aspect of your ADU are you (or will you be) most happy with?
I do enjoy the organic aspect of building and making changes as you go along, because sometimes the feel or look isn’t what you anticipated, or it doesn’t have the right feeling or flow, but those on-the-fly changes cost money. That said, I’ve designed a well thought out space with efficiency of space as the main goal. The kitchen has more effective storage space than our main house. I’ve incorporated storage in almost every available spot and still have a few spots I can come back to add interior wall shallow cabinets if I still need more.
I love the design of the master bedroom with its efficient use of closet space. I love that I thought out lighting and put so much effort into that part of the project.
What design aspect of your ADU are you (or will you be) least happy with?
My husband wanted a separate toilet room from the main bathroom, although it’s functional to have a separate toilet room, it took up space from the main bathroom.
We also lost space in the master when the stairs were added, we lost a large closet but something had to give to get stairs. We have more storage and closets upstairs now though.
What is element of your ADU, or the development process and outcome, that you are most proud of?
Storage cubbies in kitchen island built into walls, kick board drawers on every cabinet. Pot filler above stove, skylights, plumbed for outdoor shower. The incorporation of yard design as an additional living space. Cedar beam ceiling, gives sense of large volume.
What was the most surprising thing your learned during your design/build process?
When you do parts on your own, it takes longer and costs more than having a total build bid for a project.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Getting the right design for your space, making it feel like a house rather than a tiny home, expect delays and know that there is always overage costs with any project.
Editorial note from the organizers: This unit is not an ADU. It is a micro unit on a trailer. The unit may be unavailable for tours over the course of the day to allow for breaks and lunch.
ADU #5
1752 Shattuck Avenue, Berkeley
Design/Permits: Panoramic Interests
Builder: Extreme Cube
Why did you build an ADU? What different ways do you plan to use the ADU over time?
This is an all-steel prototype built for a 40 unit project of studio apartments.
What did you do to prepare for the ADU development process?
This is the 3rd generation of a micro-apartment prototype, developed for mass production on small sites in California.
How are you using the ADU now, or how will you be using ADU once it's complete?
This fully function [sic] prototype is designed for an easy connection to electricity, water and sewer.
editorial note from the organizers: It is not clear how long it would take to permit this structure and connect utilities. There are presumably a wide variety and large number of locations that it would not be allowed in. It is currently on a trailer in a parking lot and it appears to not be used for habitation at the moment. We are happy to include alternatives to ADUs on the tour to illustrate some of the options that exist for other structure types, but please do your due diligence before making any commitments.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New steel construction.
editorial note from the organizers: this is a trailer microunit. It is on a trailer.
What's the total interior square footage?
Free standing 160 SF ADU, with trailer. Can be used with or without trailer.
editorial note from the organizers: from our understanding, this is not permitted as an ADU.
What kind of heating system did you use?
Electrical [sic]
What month and year did you start the design work?
2021
What month and year did you submit the plans to the City?
Because this was prefab construction, plans were submitted to State Housing and Community Development Dept. [sic]
What month and year did you start construction?
May 2021
What month and year did you (or will you) get your Certificate of Occupancy?
Not applicable, as this is on a trailer.
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No
editorial note from the organizers: from our understanding, this is not permitted at any permanent address or by ANSI standards
What was the total cost of the project?
$100K +
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
20+ years of design interation and experience. Hard to put a price on that.
How do you think about the 'return on your investment' for this ADU?
Assuming it rents for $1,200 a mont, cost should be recouped in 7 years. .
Besides its small size, what green features did you include in your design?
All-steel construction of structure. Foam insulation and dual glassed windows. Fully furnished with specially design steel wardrobe and bed, folding dining table, and desk. Tile bath. 24/7 Energy Recovery Ventilation with Lunos System.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Super strong structure, owing to need to be able to transport and place with crane on site.
What would you do differently, if you were to start over?
Inasmuch as this is the 3rd iteration of our micro-apartment design, we are getting close to what we think is ideal for this purpose. We'd tweak the bathroom design and water heating system.
What design aspect of your ADU are you (or will you be) most happy with?
For a tiny space, this has a lot of functionality. The bed acts as a couch. The folding table allows the resident to have guest for a meal or coffee. The wardrobe can hold clothing or pantry supply. The dwelling is airy and full of light, with natural cross ventilation. There is ample storage as part of the bed and in the wardrobe and kitchen cabinets. There is a separate work area adjacent to the bed, useful for Work From Home. All in 160 SF.
What design aspect of your ADU are you (or will you be) least happy with?
The shower is a bit tight.
What is element of your ADU, or the development process and outcome, that you are most proud of?
The feeling of spaciousness and the functionality of this small, but serviceable, ADU.
What was the most surprising thing your learned during your design/build process?
The critical importance of ventilation and natural light.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Make every inch count.
Lay out everything on a floor before committing to final design.
Prototype everything.
Great design comes from iteration.
ADU #6
1225 Derby, Berkeley
Design/Permits: New Avenue
Builder: New Avenue
Editorial note from tour organizer: This unit would cost more to complete today than it did in 2018, but it is still an incredibly remarkable achievement in affordable construction! Even adjusting for inflation, we estimate this is the most affordable unit on tour without government incentives.
Why did you build an ADU? What different ways do you plan to use the ADU over time?
I built it because I wanted to be near my family and I intend to stay here. I want to be near my grandchildren. I sold my other properties in Tacoma to help buy this home with my daughter and son in law and convert the garage for myself. Fortunately they wanted me here! That’s the nice part.
What did you do to prepare for the ADU development process?
I received drawings, ideas and information from the builder and then we followed through with things that I wanted specifically. For instance the original design was to have a bedroom and I really felt that a Murphy bed would give me a good size living room and dining room.
How are you using the ADU now, or how will you be using ADU once it's complete?
I live in it. I have lived in it since it was finished.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
This is a mother in law.
What's the total interior square footage?
390, which no one believes!
What kind of heating system did you use?
It is a Bosch gas furnace, with heat and air conditioning
What month and year did you start the design work?
8/23/2018
What month and year did you submit the plans to the City?
9/2018
What month and year did you start construction?
1/5/2019
What month and year did you (or will you) get your Certificate of Occupancy?
6/2019
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No
What was the total cost of the project?
$91,550
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
I selected the windows, flooring, kitchen, Murphy bed, the entire closet system, French door, appliances and finishes in the bathroom, tile in the shower, all the interior and exterior painting, I selected the floorboards and laid the floor, we laid the stone floor in the bathroom too. $40,000.
How do you think about the 'return on your investment' for this ADU?
I couldn’t be happier! It’s wonderful. I have no home expenses. All my utilities are covered by my kids. I have no house payment.
Besides its small size, what green features did you include in your design?
This heating and air conditioning system was recommended for its efficiency. My son picked up a counter top oven that does everything g from baking to roasting to broiling. It does absolutely everything and that got me three large kitchen drawers.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
I don’t think so.
What would you do differently, if you were to start over?
No. I really wouldn’t do anything differently.
What design aspect of your ADU are you (or will you be) most happy with?
My ceiling is on an angle which is wonderful.
What design aspect of your ADU are you (or will you be) least happy with?
The concrete floor gets cold.
What is element of your ADU, or the development process and outcome, that you are most proud of?
Just the final design and the fact that it feels so much larger than anyone would imagine. Or is spacious, and open, and I have big windows.
What was the most surprising thing your learned during your design/build process?
The fact that when I questioned the smaller original windows I noticed that a lot of ADUs made without the person who lives in it that windows are small. It was important to me to have big windows.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Do it!
ADU #7
2842 Fulton St, Berkeley
Design/Permits: Type Five typefive.com
Builder: Type Five
Why did you build an ADU? What different ways do you plan to use the ADU over time?
The ADU was built as a guest house for friends and family. The owners recently relocated to the Berkeley and wanted to have a space for longer term stays.
What did you do to prepare for the ADU development process?
Spoke to our realtor, did online research, worked with Type Five to design the ADU
How are you using the ADU now, or how will you be using ADU once it's complete?
Guesthouse for friends and family
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New construction. Garage was removed in order to build the new ADU
What's the total interior square footage?
300 sq ft
What kind of heating system did you use?
Ductless minisplit with ceiling cassette
What month and year did you start the design work?
January 2022
What month and year did you submit the plans to the City?
April 2022
What month and year did you start construction?
August 2022
What month and year did you (or will you) get your Certificate of Occupancy?
March 2023
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
n/a
What was the total cost of the project?
$200,000
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
n/a
How do you think about the 'return on your investment' for this ADU?
Our realtor returned to tour our complete ADU and told us that we have added at least $250,000 in additional value to our home with this project.
Besides its small size, what green features did you include in your design?
R21 walls, R30 ceilings, R30 floor, Cool roof, NSF lumber
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
This project required a sewage ejector pump which cost 6k between labor and materials. We also removed the existing garage and foundation which cost 4.5k
What would you do differently, if you were to start over?
n/a
What design aspect of your ADU are you (or will you be) most happy with?
The large Marvin Ultimate doors and windows!
What design aspect of your ADU are you (or will you be) least happy with?
n/a
What is element of your ADU, or the development process and outcome, that you are most proud of?
The way that the ADU matches the main house in terms of paint colors was a priority. The ADU feels nicely integrated into the property.
What was the most surprising thing your learned during your design/build process?
Using a turnkey design/build firm like Type Five made the process so much simpler and stress free.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
n/a
ADU #8
3020 Benvenue Unit #7, Berkeley
Architect: Charles Kahn, AIA - Studio KDA
Builder: McDunn Construction
Why did you build an ADU? What different ways do you plan to use the ADU over time?
I saw a big, empty, unused yard behind our 5-unit building, and thought given the housing crisis, it was a terrible waste of valuable property. I also thought it would be fun to design and build an ADU or two for the space. I am the Senior Founding Principal of Studio KDA, one of the larger architecture firms in Berkeley. We design a lot of large multi-family projects, but I thought it would be a rewarding experience to do a small, custom design at the 3020 Benvenue property. Finally, I am committed to helping solve the state's housing crisis, and have been a member of the city's ADU Task Force for some time, contributing to passing the current legislation for the city. This was an opportunity to "practice what you preach".
What did you do to prepare for the ADU development process?
I am thoroughly acquainted with the ADU legislation, both statewide and locally, having contributed substantially to the drafting of both. Additionally, our firm has designed and built numerous ADU's over the years, so that experience prepared me well for this one. I also, in addition to being an Architect for a number of decades, am a Registered General Contractor, so I understand the building process.
How are you using the ADU now, or how will you be using ADU once it's complete?
We are currently renting the ADU, though I may want to live there one day.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New, free-standing cottage.
What's the total interior square footage?
1000 sf
If it is attached to additional square footage, how much additional square footage, and what is that space used for?
75 sf Storage space
What kind of heating system did you use?
Ductless minisplit heat pump
What month and year did you start the design work?
November 2021
What month and year did you submit the plans to the City?
April 2022
What month and year did you start construction?
August 2022
What month and year did you (or will you) get your Certificate of Occupancy?
September 2023
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
Not really
What was the total cost of the project?
$550,000
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
$30,000 for unbilled design work, CA oversight, minor carpentry and painting
How do you think about the 'return on your investment' for this ADU?
A great investment. We will be netting close to $40,000 annually after expenses, a 7% cap rate on the investment dollars.
Besides its small size, what green features did you include in your design?
PV, all electric design, recycled content in flooring and decking, passive solar design, low-water landscape with native, pollinator friendly planting, sustainably harvested mahogany, etc...
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Demolition of a portion of the existing garage, higher quality fixtures and finishes.
What would you do differently, if you were to start over?
I would make sure the PGE application was moving along...
What design aspect of your ADU are you (or will you be) most happy with?
I love the cathedral ceiling in the living room and the bridge overlook with its view of the distant landscape. I love the large south-facing deck and its beautiful, natural wood, deep overhanging roof. I like the flow of space and the way everything is flooded with natural light.
What design aspect of your ADU are you (or will you be) least happy with?
I wish it could be bigger. We took advantage of every inch of the 1000sf allowed, but 1200 would have given us a bigger, better second bedroom, or possibly a third one.
What is element of your ADU, or the development process and outcome, that you are most proud of?
In terms of details, I love the exposed wood elements - the structural wood beams and the mahogany details. I particularly like the handrail resolution on the "bridge".
What was the most surprising thing your learned during your design/build process?
Not a lot of surprises, pretty much went the way I thought it should.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
If you want something truly beautiful, find an architect whose work you admire and who has good experience with ADU's. Interview them and make sure that you have good communication and mutual respect. Then hire them. Make sure you communicate your needs and desires clearly and completely before they start designing, then get to it.
ADU #9
1634 Fairview Street, Berkeley
Architect: Inspired ADUs
Builder: M. Perez Construction
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We wanted to have a home for our senior years, and we wanted to help (in a small way, at least) with the shortage of housing in the East Bay. We've done major remodels on all three of our previous homes and really enjoy the process of creating beautiful, personalized homes that are built with the long term in mind.
What did you do to prepare for the ADU development process?
We did attend a couple ADU tours and did a lot of online research about the emerging process and local laws. We developed a budget (way low, as it turned out!) and looked at financing options. We researched architects, finally reaching out to Carrie at Inspired ADU's. Shortly after engaging Carrie's firm, we took out a mortgage on our paid-for primary residence, taking advantage of the then record-low interest rates.
How are you using the ADU now, or how will you be using ADU once it's complete?
We will initially rent it out, but will likely move in ourselves eventually.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
Our ADU is detached in the back yard of our existing rental property. It pushes the envelope of ADU size restrictions, constituting two stories and 1,000 square feet.
What's the total interior square footage?
1,000 sq ft
What kind of heating system did you use?
Heating and cooling is provided by four ductless minisplit heat pumps.
What month and year did you start the design work?
April 2021
What month and year did you submit the plans to the City?
August 2022
What month and year did you start construction?
We broke ground March 20, 2023
What month and year did you (or will you) get your Certificate of Occupancy?
Hopefully, October, 2023
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No particular issues here, but it took longer than we expected and cost more in terms of various fees and required supporting soft costs (surveying, etc.)
What was the total cost of the project?
$500,000 plus
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
Approximately $12,000 for interior and exterior painting.
How do you think about the 'return on your investment' for this ADU?
We should be cash-flow neutral on day-one. We consider it an investment for our kids, as home values in the bay area have risen steadily and will probably continue to do so.
Besides its small size, what green features did you include in your design?
High insulation values, space and water heating via heat pumps, Hardieboard siding. All electric.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
We did choose relatively expensive windows, finishes, fixtures, and appliances.
What would you do differently, if you were to start over?
I would do more research on the anticipated costs, as they turned out to be significantly higher than we first anticipated.
What design aspect of your ADU are you (or will you be) most happy with?
The way it wraps around our large Black Walnut tree and the ample natural light throughout.
What design aspect of your ADU are you (or will you be) least happy with?
It really took up most of the backyard.
What is element of your ADU, or the development process and outcome, that you are most proud of?
We're proud of the overall design that we worked out with Soufyane at Inspired ADU's.
What was the most surprising thing your learned during your design/build process?
We had a lot of experience with the construction aspects, but I was surprised by how much work there was around the permitting process, even though ADU's are exempt from many requirements that other new construction has to go through.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Get professional help early on, and talk to people who have gone through the process. Choose your contractor carefully.
ADU #10
5932 Whitney Street, Oakland
Architecture: Carrie Shores Diller, Inspired ADUs, https://inspiredadus.com/contact-us
Builder: Rolf Bell, Green Living Builders, LLC, https://greenlivingbuilders.com/about-us/
Why did you build an ADU? What different ways do you plan to use the ADU over time?
It's largely our retirement plan. It will provide income to cover the mortgage of the main house and, as it's ADA compliant, will provide us a place to live when we need it. We will then rent out the main house.
What did you do to prepare for the ADU development process?
Searched online; met with a few architects; met with a builder friend (who ended up being our contractor); secured a secondary mortgage (HELOC) from our credit union; communicated our intent with contiguous neighbors.
How are you using the ADU now, or how will you be using ADU once it's complete?
It is a rental property; ideally with 6-month minimum rental agreements.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
Garage was demolished and the ADU constructed in its place.
What's the total interior square footage?
618 sq ft
What kind of heating system did you use?
ductless minisplit, radiant heating in the bathroom only, only electric
What month and year did you start the design work?
October 2020
What month and year did you submit the plans to the City?
February 2021
What month and year did you start construction?
April 2021
What month and year did you (or will you) get your Certificate of Occupancy?
Job card signed September 2021
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
The heat pump was originally placed within the 4' setback and needed to be moved.
What was the total cost of the project?
$350k
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
I estimate my sweat equity at $15k - I did the interior and exterior painting and some minor finishing work.
How do you think about the 'return on your investment' for this ADU?
With construction happening during the peak of the Covid pandemic, the cost was $350k rather than the estimated $250k. Nevertheless, I hope to get it all paid back in 5-6 years after which it'll provide important retirement income.
Besides its small size, what green features did you include in your design?
solar panels and cool roof; high quality windows, heat pump with minisplits
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
The interior stair to the loft was pricey ($4k); garage demolition ($4.5k), heat pump and minisplits ($9.5k), sewer lateral ($5.3k)
What would you do differently, if you were to start over?
Seal the floating floor (I was told it was not necessary and found out differently)
What design aspect of your ADU are you (or will you be) most happy with?
Great light with a high ceiling in the main living/dining/kitchen area
What design aspect of your ADU are you (or will you be) least happy with?
The floors. They look good but are not sufficiently resistant to water spills. I don't like the look for the minisplits, but I made that choice.
What is element of your ADU, or the development process and outcome, that you are most proud of?
Beautiful stair, radiant floor heat in the bathroom, great natural light, nice open living/dining/kitchen space.
What was the most surprising thing your learned during your design/build process?
The high costs of everything! There were a LOT of details and it was a VERY good thing that I was working from home (COVID-inspired) so that I could be on site pretty much every day to make the necessary last- minute decisions that inevitably arose.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Work with an architect and builder with whom you feel you can communicate and work with well.
ADU #11
6030 Chabot Rd, Oakland
Architecture: Patty Haight, http://patriciahaightarchitecture.com/
(Patty was with https://www.sf-arc.com/ at the time)
Builder: Severin Oliver, https://oliverbuilders.com/
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We wanted to add a guest house to replace a dilapidated garage. A proper guest room was one thing that was missing from our house from the time we first moved in, and we were using the garage only for storage and not for parking. We thought the ADU could also be a potential source of revenue in the future as a rental.
What did you do to prepare for the ADU development process?
We met with a few architects and decided to go with the same builder who did our house remodel. Our architect was also one we had worked with previously in San Francisco. We had a rough idea of budget, and talked with the architect about options for size, location, storage options, and how to work within zoning rules. We found that we could add extra storage around the back of the ADU after building it, since a storage shed is allowed anywhere on the property, and this space has been very useful.
How are you using the ADU now, or how will you be using ADU once it's complete?
The ADU became the perfect home office when the pandemic hit and I started working from home. Our daughter has also used it as a study at times. We still use the ADU as a guest house or extra bedroom; occasionally we use it for get togethers. We've used it as a quarantine space when one of us has been sick, as well.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
This was a replacement for a previously existing garage. We tore down the garage completely and built from scratch.
What's the total interior square footage?
About 360 sq ft
What kind of heating system did you use?
radiant floor heating (via hot water)
What month and year did you start the design work?
July 2016
What month and year did you submit the plans to the City?
Jan 2018
What month and year did you start construction?
April 2018
What month and year did you (or will you) get your Certificate of Occupancy?
November 2018
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
no big issues
What was the total cost of the project?
$375,000
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
$0 we did a lot of work evaluating designs, choosing finishes, cabinets, etc., but didn't do any physical work on the project
How do you think about the 'return on your investment' for this ADU?
hard to put a number on it, but it has been very well worth it. Having the extra space during the pandemic when we were all home every day was hugely valuable.
Besides its small size, what green features did you include in your design?
I don't remember... We did go with a portable induction burner rather than a gas stove.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
I don't remember anything notable. We did need to run gas and electricity lines out to the ADU, and tear down the old garage. We did repave part of the driveway as well because the footprint changed from the old garage.
What would you do differently, if you were to start over?
We might add a little more ventilation. We can always open the windows, but with two sides fully closed, it can limit the airflow. I think I also might go all electric and skip the gas line, especially now that we've added solar panels on the main house.
What design aspect of your ADU are you (or will you be) most happy with?
I like the big windows facing the yard; that has been a great place to put a desk
What design aspect of your ADU are you (or will you be) least happy with?
We are pretty happy with it all
What is element of your ADU, or the development process and outcome, that you are most proud of?
I'm very happy with the storage space we were able to add; I feel like we store as much in there now as we used to store in the whole old garage. I really like the look of the ADU, matching the house, but with a bit more of a modern edge. And I love how much utility we were able to fit into a small space.
What was the most surprising thing your learned during your design/build process?
We had no idea how many things we would end up using the ADU for!
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
We took our time with design, and I think that worked out well -- we were able to go back and forth and really figure out what would work.
ADU #12
5453 Lawton Avenue, Oakland
Architect: Inspired ADUs, https://inspiredadus.com/
Builder: Buildzig, https://www.buildzig.com/
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We built an ADU primarily to allow Katie's parents to live with us part-time and have access to their own independent unit. They have been the primary caretakers for our toddler son (and will be for our newborn daughter as well), but live in Sacramento, so a daily trip between their house and ours is not practical. Instead, we were seeking a way for them to spend part of the week at our house but still maintain some independent space.
An additional benefit we imagined for the ADU would be having a fully separated "flex space" that can be used for short or longer term guests, office, gatherings, etc., or even for rental purposes, if needed at a later date.
We also imagine the ADU could eventually turn into a living space for one of our children in their teenage years or beyond.
What did you do to prepare for the ADU development process?
Andrew works in affordable housing development and brought some professional experience to the planning and development process.
We received bids from three architects. We worked with one architect on initial conceptual development, and ending up switching to Inspired ADUs. We went back and forth on multiple concepts and also consulted with a friend who works in the architecture/planning field.
We also received four bids from contractors and negotiated prices and contractual language.
Andrew coordinated closely with the the contractor and architect to try to support a smooth planning/permitting/inspection process.
We consulted with a financial advisor to try to develop a budget and spending plan.
How are you using the ADU now, or how will you be using ADU once it's complete?
Katie's parents spend on average four days/three nights a week in the ADU.
Katie will often work in the ADU during her at-home work days, since it allows for separation from our children if they are in the house.
When we have guests visiting over the weekends they will use the ADU.
When hosting gatherings at our house we often use the ADU, since its very integrated with our backyard.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
Garage conversion
What's the total interior square footage?
400 square feet
What kind of heating system did you use?
Minisplit
What month and year did you start the design work?
August 2020
What month and year did you submit the plans to the City?
January 2021
What month and year did you start construction?
August 2021
What month and year did you (or will you) get your Certificate of Occupancy?
May 2022
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
There was some confusion with the City over whether our footprint would be allowed. The plans called for our ADU to replace the garage at the existing lot line based on grandfathering rules, even though a new construction ADU would require a four-foot setback. Eventually we were allowed to build according to this plan.
There was also some confusion over whether a demolition permit was required for our project, which created some delays with inspections.
Lastly we ran into an issue with our upstairs portion of the unit -- the rules technically don't allow for bedrooms at that height, which created some confusion with our inspectors and required that we consider the area a "storage space."
What was the total cost of the project?
$235,000
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
n/a
How do you think about the 'return on your investment' for this ADU?
We don't have plans to rent out the ADU. Our only real financial goal would be to get the value of the investment back if we sold our house in the coming years. There is also the financial value of avoiding childcare costs by having Katie's parents available on-site, which may value up to $100k when all is said and done.
Besides its small size, what green features did you include in your design?
Hybrid water heater, which also replaced the existing water heater for the whole house.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Nothing particular
What would you do differently, if you were to start over?
Use my personal network a little more extensively for some input on the designs.
What design aspect of your ADU are you (or will you be) most happy with?
We love the open concept of the main floor and the way its integrated into the backyard.
It has very high ceilings and a lot of light that pours in throughout the day.
What design aspect of your ADU are you (or will you be) least happy with?
The stairs to the second story are very steep, which makes it hard for older folks to access the bedrooms.
The alignment of vanity in the bathroom wasn't able to match the original design which makes that space a little awkward
What is element of your ADU, or the development process and outcome, that you are most proud of?
I love the general experience of walking into the main floor and how it feels so much larger the 300 square feet on the ground level.
The window above the front entrance is shaped like the house which is a really nice touch.
What was the most surprising thing your learned during your design/build process?
I think the city process was very challenging. All cities have their challenges but Oakland seems like it was particularly disorganized and under-resourced.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Get as many quotes from contractors as possible and ask a ton of questions on the numbers -- i think they have different approaches so you can get numbers that are all over the map.
Make sure you work with a team that knows the City staff and rules really well. Our GC and architect both did and it helped overcome some substantial roadblocks.
If you can, try to complete other key projects simultaneously so you can knock some major things out simultaneously. For example, we also completed a lot of landscaping work, which added to the workload, but we felt like there was some economy of scale in doing it at the same time and planning it around the ADU. I also wished i had spent the time to figure out solar installation at the same time as the ADU.
ADU #13
4280 Montgomery Street, Oakland
Architect: Inspired ADUs, https://inspiredadus.com/
Builder: Buildzig, https://www.buildzig.com/
Why did you build an ADU? What different ways do you plan to use the ADU over time?
I built my ADU with the idea that I would live in it. I felt that I was ready to downsize, just have less house to deal with. I love my neighborhood and have lived here a long time. So it worked out that my daughter was willing/happy to move back to her childhood home and I built a cottage in the backyard for me to live in. It is nice to be close to family and I get to see my granddaughter every day. I would not have built this if my daughter did not want to live in the front house.
What did you do to prepare for the ADU development process?
I looked online a lot. I looked at the plans of either prefab or ones that were already drawn up. I looked at ADUs mostly from people I know (there are a lot of ADUs in my neighborhood) or construction I would see when walking the dog. I tried to picture what it would look like in my backyard and if I could live in it.
How are you using the ADU now, or how will you be using ADU once it's complete?
I live in it. My daughter and her family live in the front house.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
This is new construction, free standing.
What's the total interior square footage?
16x33 = 528 square feet
What kind of heating system did you use?
Ductless minisplit
What month and year did you start the design work?
I think it was November 2020
What month and year did you submit the plans to the City?
4/19/2021
What month and year did you start construction?
I think it was August 2021
What month and year did you (or will you) get your Certificate of Occupancy?
May 2022
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No
What was the total cost of the project?
$275,874.
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
None
How do you think about the 'return on your investment' for this ADU?
I think this ADU does/will increase the value of my property that won’t be realized until it is sold. Meanwhile I get to live there.
Besides its small size, what green features did you include in your design?
n/a
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
I don’t know. The sewer lateral cost $18,000
editorial note from tour organizer: This ADU cost excludes extensive exterior hardscaping to make an accessible pathway that is on grade with the driveway.
What would you do differently, if you were to start over?
I would probably have different doors.
What design aspect of your ADU are you (or will you be) most happy with?
I like the airy design and big windows, lots of light. The kitchen is big enough so that I can cook and even have a helper.
What design aspect of your ADU are you (or will you be) least happy with?
n/a
What is element of your ADU, or the development process and outcome, that you are most proud of?
None
What was the most surprising thing your learned during your design/build process?
I think I was a little surprised every step of the way. I had never been involved with a construction project before.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Be sure of what you’re trying to do. Are you going to happy giving up your yard? Having someone else live on the property?
ADU #14
78B Fairview Avenue, Piedmont
Architect: Inspired ADUs
Builder: McDunn Construction
Why did you build an ADU? What different ways do you plan to use the ADU over time?
After my wife died I did not need to live in the main 2200 ft2 house as a part-time resident. Building the ADU allowed me to continue to live in this neighborhood where I have many friends and to earn retirement income by renting out the main house. It also gives me options as I grow older including moving elsewhere and renting or selling both the main house and ADU separately or together or perhaps selling the main house and maintaining the ADU for rental and/or continued part-time occupancy.
What did you do to prepare for the ADU development process?
Reseached ADU plans and options online and spoke to other ADU owners and contractors recommended by my architect and friends who knew of people who had built ADUs
How are you using the ADU now, or how will you be using ADU once it's complete?
Primary winter residence
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New construction
What's the total interior square footage?
770 sq ft
If it is attached to additional square footage, how much additional square footage, and what is that space used for?
863 sq ft, built in part on land where a garage stood
What kind of heating system did you use?
electric heat pump
What month and year did you start the design work?
March 2020
What month and year did you submit the plans to the City?
June 2020
What month and year did you start construction?
October 2020
What month and year did you (or will you) get your Certificate of Occupancy?
August 2021
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
No, except there were some delays around my solar contractor getting the appropriate permits for the required solar installation (which was allowed to go on the main house).
What was the total cost of the project?
$550,000 + 6-8 weeks of my time working over the course of 1.5 years with my architect and building and solar contractors
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
I did none of the actual physical work on the project myself.
How do you think about the 'return on your investment' for this ADU?
Over a five to fifteen year period I figure that the cost of the ADU and landscaping will enhance the overall value of the property (or at least not detract from it). During that time I will earn rental income from the main house and live in the ADU part-time where main my ongoing costs are incremental property taxes and insurance and low energy bills (offset by on-site solar power generation)
Besides its small size, what green features did you include in your design?
Induction cooktop and tankless natural gas water heater. I also would have installed an expensive electric heat pump water heater if I'd known that the cost of running a gas line to the tankless natural gas water heater would be close to $3,000!
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Design review in Piedmont requires that the external architectural features of an ADU match those of the main house on the property. That is not true in many other municipalities. I would estimate that Piedmont's process increased my cost to do the project by $15,000 to $25,000 relative to what it might have cost if my property had been located in Oakland for example. This approach did result in a better looking ADU which I'm quite happy with, but there was a cost associated with this approach!
What would you do differently, if you were to start over?
Made better, more informed choices, regarding radiant floor heating and electric heat pump water heating
What design aspect of your ADU are you (or will you be) most happy with?
Spacious feeling for a small footprint, lots of natural light , beautiful modern design that promotes indoor/outdoor living.
What design aspect of your ADU are you (or will you be) least happy with?
Initially I wanted electric radiant floor heating but chose not to install it (except in the bathroom) because of Title 24 requirements and cost. Without radiant floor heating the floors, which are on a slab foundation, are cold in the winter and the heat pump with indoor ceiling units has to be set at a higher temperature to maintain comfort.
What is element of your ADU, or the development process and outcome, that you are most proud of?
I hadn't figured in the cost and need for landscaping and surprise sewer work which added significantly to the total project cost. Aside from sewer and landscaping work the project was completed in a reasonable time and within budget given that design and construction occurred during the pandemic.
What was the most surprising thing your learned during your design/build process?
Talk to landscaping contractors early in your planning process if you are intent on knowing what your total project cost will be.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
If you want something truly beautiful, find an architect whose work you admire and who has good experience with ADU's. Interview them and make sure that you have good communication and mutual respect. Then hire them. Make sure you communicate your needs and desires clearly and completely before they start designing, then get to it.
Editorial Note from Organizers: THIS ADU IS UNDER CONSTRUCTION. Wear close-toed shoes and be very careful when visiting. Follow all safety precautions required by the contractor on site.
ADU #15
1033 Winsor Ave, Oakland
Design/Permits: Design Draw Build designdrawbuild.com
Builder: Zeus Design Build zeusdesignbuild.com
Why did you build an ADU? What different ways do you plan to use the ADU over time?
We are motivated to build the ADU to do something creative with our large yard, to provide a place for extended family to live, to pursue our interest in architecture and building, and to add housing to our neighborhood. Building the ADU also makes sense as an investment. We think we will be able to rent the ADU to family and friends at below market rate and still achieve a payback after 15 years.
What did you do to prepare for the ADU development process?
We have been interested in architecture, urban design, and land use planning for most of our adult lives. We had considered building an ADU years ago, but the requirement to build off street parking for every residential unit was a dead end for us. Our perspective changed when Oakland, and eventually California, updated ordinances and legislation regarding off-street parking requirements so that no new off-street parking was required. Once we decided to build an ADU we reached out to our friends at Zeus Design Build and Medium Plenty for advice on finding architects and understanding what was possible and feasible.
How are you using the ADU now, or how will you be using ADU once it's complete?
The ADU will be for a family member. If she changes her mind about living here we will rent it to a friend.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
New construction
What's the total interior square footage?
671 sq ft total
What kind of heating system did you use?
ductless minisplit
What month and year did you start the design work?
August 2022
What month and year did you submit the plans to the City?
March 2022
What month and year did you start construction?
May 2023
What month and year did you (or will you) get your Certificate of Occupancy?
March 2024
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
We had no problem getting zoning approval
What was the total cost of the project?
$400,000
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
$150,000 for project management, soliciting trade specialists, managing subcontractors, managing permits and inspections, assisting GC with all elements of construction, custom windows, roofing, floors, cabinets, sourcing appliances and finishes, installing appliances, paint and plaster, waterproofing, wood siding, custom interior doors, tiling, baseboards, lighting, and making coffee for sleeppppy construction workers.
How do you think about the 'return on your investment' for this ADU?
We think we can get our ROI in 15 to 20 years. Afterwards we will continue to rent the unit to friends or family or potentially move into the unit ourselves and rent the main house. We plan to rent below market rate and still we think this is a sound investment.
Besides its small size, what green features did you include in your design?
Lots of energy efficiency including efficient appliances and spray foam insulation.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Three-panel folding door (17k), VG cedar siding (10k), western maple ceiling and floors (5k), polished black concrete floor with inlaid brass (7k).
What would you do differently, if you were to start over?
Line up contracts with subcontractors early because many trades are in high demand and it is not fun trying to find a new roofer or electrician late in the game. Get multiple bids and have one or more back-up subs. Don't every rely on verbal contracts and start dates. Get a reliable and experienced builder to help you navigate the construction management process, it is worth more than you pay them. Understand the lead times for critical materials (for example, windows currently have a 5-6 lead time, some specialty building materials are not available locally and need to be shipped)
What design aspect of your ADU are you (or will you be) most happy with?
Big windows and lots of sunlight, wood siding, high ceilings, modern appliances, indoor/outdoor continuity, clean and simple modern design.
What design aspect of your ADU are you (or will you be) least happy with?
Limited storage space, concerns about the special care that is required to weatherproof modern building designs (i.e. lacking eaves, large windows)
What is element of your ADU, or the development process and outcome, that you are most proud of?
It will look beautiful and will feel so relaxing to live there.
What was the most surprising thing your learned during your design/build process?
Complying with codes and other requirements regarding adding new electrical service (total nightmare), 2) building a sewer line and replacing existing sewer (total nightmare with poop), 3) how complicated waterproofing is. More specifically, many requirements for certain project elements are not easy to understand until an inspector arrives to unsympathetically tell you you did everything wrong and you need to tear it all out and start over.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Many of the responses in this survey offer advice, which I won't repeat here. In addition... Work with an architect with construction experience. Work with a builder who understands design and architecture, and all elements of construction. take time to research design ideas on your own. Take an active interest in the project if you are able, don't just hire a GC and hope it turns out exactly as you imagine. Don't settle for suboptimal options (unless you are truly out of money), try to make it exactly the way you want it and fully interrogate nay-sayers. Carefully weigh the advice you get from people based on whether they are actual experts or are in the building industry but have limited experience with the specific trade in question (i.e. engineers are not design professionals, plumbers are not financial advisors). Come to terms with yourself with whether you are making a *special* building or just a simple rental, and build accordingly without hesitation. Don't work with people who aren't helping you achieve project goals.
ADU #16
1427 e36th St., Oakland
Architect: Nathaniel Muhler https://www.wit.studio/
Builder: Gabriel Castillo
Why did you build an ADU? What different ways do you plan to use the ADU over time?
What did you do to prepare for the ADU development process?
I spent a few years brainstorming, then went on a tour with Kol from https://accessorydwellings.org/
How are you using the ADU now, or how will you be using ADU once it's complete?
My wife and I lived in it for 2 years once it was completed, but recently had a baby and moved out. We're now renting it and I plan to keep it as a rental for the long term.
How would you describe the ADU Type (detached/attached, conversion, prefab/stick-built, etc)?
Detached, new construction.
What's the total interior square footage?
650 (this is off the top of my head, will need to verify later))
If it is attached to additional square footage, how much additional square footage, and what is that space used for?
Not sure if this counts but we added a small (~6x9) attic space for storage over the bathroom as well as a crawl space for storage. All in all about ~350sqft of storage. Also, the loft is about 100sqft and is not included in the square footage calculations
What kind of heating system did you use?
hydronic radiant floor heating. The downstairs uses pex directly in concrete, the upstairs uses pex in warmboard subfloor. Water heating is provided via an outdoor air-to-water heat pump that also provides the home with domestic hot water.
What month and year did you start the design work?
July 2016
What month and year did you submit the plans to the City?
August 2017
What month and year did you start construction?
June 2018
What month and year did you (or will you) get your Certificate of Occupancy?
May 2020
Were there any significant issues with planning/zoning BDS that made your project more difficult to get approved?
Biggest issue was that there was a major overhaul done to the laws around ADUs in the state of California (I think in 2017?). This resulted with Oakland implementing a lot of changes (good changes) and temporarily halting approvals
What was the total cost of the project?
~$650k
What do you estimate your own sweat equity to be worth on this project? What parts of the work did you do yourself?
~$100k
How do you think about the 'return on your investment' for this ADU?
It was a poor financial investment at the time which may pay off over time. For example, I could have used that same money for buying a standalone property and saved myself the time and headache. The real return from the project was having such a great creative outlet and the experience of building a house.
Besides its small size, what green features did you include in your design?
omg, so many details. Perhaps on another day with more time I could list them out and follow up.
What, if any, special project costs did you have that caused your project to cost more than another comparable project would normally cost?
Retaining walls and the odd shape of the house that was required in order to meet city zoning laws were a huge extra cost. I would imagine that perhaps accounts for ~50% of the cost.
What would you do differently, if you were to start over?
At the end of the day, it was an amazing experience and while there were definitely some very very low points, I'm not sure at the moment, what I would have done differently. I'm very happy with the results. My architect, Nathaniel and my lead carpenter Paul, were rockstars.
What design aspect of your ADU are you (or will you be) most happy with?
What design aspect of your ADU are you (or will you be) least happy with?
The roof. I hired a team that does custom cut metal panels which I thought would be ideal given the unique shape of the house, but ultimately, it's one of the aesthetic aspects of the home that looks sloppy and still really bothers me
What is element of your ADU, or the development process and outcome, that you are most proud of?
Finishing it :)
What was the most surprising thing your learned during your design/build process?
Decisions decisions, sooooo many decisions.
What advice would you offer someone else who wants to build the same kind of ADU that you built (basement, garage conversion, above the garage, new construction etc.)
Spend a lot time in the design phase, way more than you think you need. It's much easier and cheaper to iterate on designs than it is to iterate during construction. The same thing goes for planning, the more you plan up front, the faster construction will go, which will also save money.
You will spend a lot of time talking to, solving problems with, and maybe even disagreeing with the team of people you hire. Take this into account when hiring them.
ADU #17
2522 11th Ave
Design/Permits:
Builder:
Editorial note from the organizer: this was a recipient of the CalHFA $40,000 ADU Grant via CCEDA and CCEDA will be on site during the ADU tour to talk about that process