ADU — where and how to start?

We have a dilapidated “garage” which turns out it was never a garage but a carport that the previous owner put up a wall to enclose it. concrete slab is torn up and in a bad shape. Water seeps in from the uphill neighbor. It’s where things go in to become garbage. I am afraid to go in because of rat poop and dust. Dark, dingy, dusty and a real mental drag.  I dream of turning this into a bright and usable space. An enclosed and weather protected storage would be fine but it would be amazing to have a flexible space for working from home, guest bedroom or dare I dream, a family play space. As we are cramped in our small 2 bedroom house with no storage space and small backyard, I look at this wasted space and get frustrated that it isn’t more useful.

I have no idea where to start to make my dream a reality. I don’t want to start meeting with architects when I don’t even know how much I need to budget. I don’t have hundreds of thousands of dollars just sitting in the bank, so I would like to have an idea of how much something like this costs so that I can start saving for it and figure out how to come up with the funds. Do people just borrow against their current equity?

Moving to a bigger place will be easier but I think that might be more expensive. We are in Oakland and I don’t think we want to move to Antioch/Clayton or beyond to get a house we want within our budget.  But I don’t know.

I think I need a designer / manager who will guide us through the entire process (land survey, permit, etc) But I don’t even know what I dream of is possible. 

Any tips on where to start would be very much appreciated. 

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RE:

If you want to ball park, I would apply a cost per sf calculation to your garage size. So if you have 500 square ft at $600/sf its a $300 job. I'm not sure what current prices are per square ft but I wouldn't be surprised with the current environment if its around $600. Also if your garage isn't a permitted garage, you may have issues getting an official ADU permit and will have to go the much harder route (aka more $ and time). 

RE:

Hi there. I live in Oakland and had a similar situation - a garage that was too small to park in, filled with junk and also rats. The floor was sound and so was the roof etc, so the structure was ok. I converted the space to a “bonus room” - really a family room which we badly needed. I used a structural engineer, a licensed contractor and myself. No architect. I wanted it to be permitted but the ceiling slopes too much and I needed to keep my WD up there, which would not have passed the permitting. So we just did everything rigorously to code, took pix of the process (for a future buyer). Btw I’ll give you 2 pieces of advice. I wanted to add a duct to heat the space from our main heater, but I spoke with several heater guys and they said that will not be approved bc Oak fears you’ll make it into a multi family dwelling. So we installed amazing little wall heaters that look and work great. We had to add a new circuit. Due to the slopes ceiling we also stumbled with insulation - code is confusing. In fact much of what you read online is wrong for alameda county. I consulted about 6 insulation companies and went with foam in the correct R that meets code. I recommend foam if you raise the ceiling. Also btw before even starting this I spoke to several local realtors to get their take re resale, which is what will eventually matter. All said go for it. I kept the space easy to convert back to a garage (just change the door), and right now we are very happy with this decision. The total cost has been about $22k for a playroom with around 180 sq ft. It might have cost $27k if we’d done it with permits. 

RE:

East Baker Construction does just that. They came to our house and had incredible suggestions and forethought. We aren’t ready to do everything yet since our toddler is giving us a run for our money. East Baker is new so their availability is good and they’re competitive in costs. 

RE:

Sadly the great institution first known as the Owner-Builder Center (later the Building Education Center) in Berkeley has gone the way of the nineteen-sixites DIY movement. As a card carrying member of that movement, and a successful owner-builder, I can steer to some cheap and free resources. An action plan is first gathering information, second learning what is feasible under Oakland zoning and 'or CA ADU law, third obtaining funding, and lastly hiring architect and getting plans.

First you need to go to the County of Alameda assessor and obtain the Building Record for your property. It will show the history, a little map of the permitted buildings, etc. Also get all the records from Oakland Planning Department.

Meanwhile you need to ponder your ideal replacement structure, whether ADU, accessory building, garage etc.

You could start to think about funding. Do you have enough equity in your home for a home equity loan? Has your home appreciated enough for a cash-out refinance to build the project?

I demolished an old garage with a dirt floor, and built a two-story accessory building with habitable space on the second floor. That cost me $150,000 about ten years ago.

Also join some Face Book pages such as  How to ADU,

Good luck

RE:

We knocked down an old garage like yours and built an ADU several years ago. Our initial budget was $100,000 but cost ended up closer to $200,000, and that was even with us putting in some sweat equity.  We do love the space, and we even enjoyed most of the process of creating it.  It does take over your life for a while, and there are stresses involved. The most difficult part was the permits and working with the city (Berkeley).

We interviewed 6 or 7 architects early on, and speaking with them on site helped us think through what we wanted. Each did a 1 hour meeting free of charge, and had the ability to connect us with builders. You might also look into partially or fully pre-fab options that you can find in places like Dwell magazine. Depending on your lot, one of those might work for you, and then you won't need an architect.

Good luck!

RE:

I actually am just now completing a similar project, although my ADU was built in my unfinished, walkout basement. I live in Oakland.
I began planning this late in 2019. I started by getting an estimate from a design build firm (Sticks and Stones in Berkeley) I’d worked with on a much smaller project a few years ago. 
Construction began in January 2021 and is wrapping up now.

Feel free to contact me through the moderator if you like. I’m happy to answer any questions. Best of luck with your project.