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ADU and DADU

What is an ADU, and what is a DADU? Ryan Adanalian explains the ins and outs of Accessory Dwelling Units and Detached Accessory Dwelling Units (according to the City of Seattle), with an example of a DADU by Board & Vellum featuring a sliding wall to help solve the many challenges of a small space.

Ryan Adanalian

March 10, 2015

What is an ADU? What is a DADU? Why does everything have to have an acronym? Some of these questions will be answered in this post and the acronym question can be answered, ironically, in another post by our fearless leader, Jeff. Personally, I try to avoid acronyms at all costs but sometimes they're unavoidable. OK, enough about acronyms, let’s get back to what this post is all about: ADU’s and DADU’s.

An ADU (accessory dwelling unit) is a separate living area within a house, often with a full kitchen and separate entry. A DADU (detached accessory dwelling unit) is a separate living space that is not attached to the main house. DADU's are often called backyard cottages or mother-in-law apartments. I was talking about these with my mom the other day, and she said: “You’re not going to stick me in your backyard storage shed!” Ha ha. The funny thing is, there are a lot of great designs out there and you wouldn't believe it, but they actually are the size of a shed. Lots of people use ADU’s and DADU’s for all kinds of things such as art studios, offices, play areas, or apartments that get rented out. You may be thinking that these are not really “living spaces”, but the City of Seattle classifies a “living space” as a heated space. If you have heat in your studio or office it is technically a “living space."

Here at Board & Vellum we love designing small spaces. It’s a fun challenge to fit lots of program into a confined space. Not too long ago, a client came to us wanting a DADU and this project had quite the program. We had a footprint of about 340 SF to work with and a lot to fit into it, so we had to use every single square inch. The clients wanted a workshop, office, kitchen, full bathroom, dining room, yoga studio, and bedroom, with a reading area / dressing area. A very ambitious project!

We quickly realized that we didn't have enough room to make all those different spaces, so we considered how we could use the space outside versus the inside space. The solution for the workshop was to install two large swing doors that concealed a workbench and tools. The bench could be pulled out and used on the driveway, turning the driveway into the workshop (see above, the first image for workshop doors). For the interior, we designed one large open space that can adapt to fit the clients' needs. It's not easy to do yoga while working in an office, reading, and cooking all at the same time, so what we came up with was a sliding wall. Yes, that's right: a wall that moves.

In the above image, you can see that we tucked the kitchen under the stairs and used all the void space for storage.

When the sliding wall is pushed toward the kitchen, an island folds down creating a work surface. Behind the island is a TV on a swing arm that can be viewed from the dining table. The office is tucked behind the sliding wall, and there are 2 large built-in cork boards with a small desk.

When the sliding wall is pushed all the way back against the bookshelves, it really opens up the space. Now there is plenty of room for yoga. You can also see in this image where we located the bathroom. We were able to fit a shower, sink, toilet, and washer and dryer.

Here is another image of the kitchen with the dining table and stairs. On the back side of the stair landing (where the lady in the pink shirt is standing/ staring at the wall) we have more storage under the stairs.