New sedge backyard cottage: 3 bedroom DADU

At 997 net square feet, the Sedge Cottage is a highly livable footprint that provides well-daylit space for living, necessary storage, flexibility on many sites, and two covered outdoor porch spaces. Within its compact form, the design features three bedrooms and two baths, a galley kitchen with a peninsula and plenty of storage. It features a bedroom and 3/4 bath on the main level that works well for an aging parent, as a guest room or work-from-home office. Standard, wood-frame construction, vented shed roof, slab-on-grade foundation, the careful placement of windows, and a simple exterior allow for low-cost construction without sacrificing durability, function, or style.

The design is under the height limit and can fit on the smallest lots, around trees, or on sloped lots, with space for adjacent parking if desired. The outdoor covered area is perfect for a BBQ and the cottage can be oriented toward the principal residence for multi-generational living around a courtyard. The front porch clearly marks the entry of the accessory dwelling.

The design targets 4-Star Built Green, with details for reduced air infiltration, energy-efficient heating, cooling, and water heating systems, passive solar heat gain in window/shading in summer, low-VOC finishes, no fossil fuel appliances, and all LED lighting.

See more at CASTcottages.com

New Sitka Cottage: 3-bedroom DADU

At 1,000 net square feet, the Sitka Cottage features three bedrooms and two baths upstairs, an open living room and kitchen, storage, and an additional powder room tucked away on the first floor.  It fits flexibly on many sites with a walk-out terrace off the living room/kitchen. The three bedrooms upstairs are reasonably sized and work well for a family. Standard, wood-frame construction, vented shed roof, slab-on-grade foundation, careful placement of windows, and a simple exterior allow for low-cost construction without sacrificing durability, function, or style.

The design is under the height limit and can fit on standard to small lots, around trees, or on sloped lots, with space for adjacent parking if desired. The cottage can be oriented toward the principal residence for multi-generational living around a courtyard. The front door is on the corner and can be placed on either the short or long side of the design, depending on site orientation.

The design targets 4-Star Built Green, with details for reduced air infiltration, energy-efficient heating, cooling and water heating systems, passive solar heat gain in window/shading in summer, low-VOC finishes, no fossil fuel appliances, and all LED lighting.

See more at CASTcottages.com

Cedar Cottage, originally designed for the Phelan family

Recently, Seattle put out a call for lower-cost designs to be ‘pre-approved’ for building permits. One of the biggest challenges for backyard cottages is the uncertainty and permitting difficulty for many people who may never have taken on a big project like this before. CAST answered the call, putting together four designs ranging in size and features, derived from our long experience with the backyard cottage market. Here is a preview of the four models, each has its own special hook—sloped lots, accessibility, expandability, or super small size:

Cloud Cottage, 481 sf footprint, multiple configurations from studio, or 2 story version with studio over garage, 1 bedroom or 2 bedroom.

Kestrel Cottage—one or optional two bedroom (not shown here), all on one level for accessibility and aging in place.

Crow’s Nest, original design for Matt and Amy Stevenson, adapted for Seattle’s Pre-Approved Cottage program

Over the next month, regardless of what this City does, CAST will be developing some or all of these designs and making them available for purchase with an agreement to use CAST for the site specific engineering, permitting and zoning work. If you are interested in finding out more, contact Matt@CASTarchitecture.com.

Now that the new legislation is in place, it is time to upload an updated Quickstart Guide for 2019. Keep in mind that we couldn’t get too deep into the weeds here, so if you have questions, please contact us and we can walk you through the changes in more detail.

Link to PDF

Steelaway Cottage, by CAST architecture 2018

To celebrate the final Environmental Impact Statement that came out last week, we’d like to highlight some of the less obvious but clear reasons for progressive Seattle to embrace the new ordinance covering Accessory Dwellings.

1. Many ADUs end up being affordable, even if they are admittedly expensive to build. I have made the case over and over that we should approach ADUs with our eyes open as to the cost and not put too much faith in them as a cure-all for our housing crisis. But, in surveys collected from Vancouver, Portland, Ashland, Eugene, Edmonton, the Bay Area, a large percentage (generally around 20-25%) of accessory dwellings end up being rented for nothing, very little or well below market rate. Voluntary affordability, where the owner has prioritized the benefit of having family, friends, or even good tenants as neighbors over the potential rent they could demand if they were more ruthless landlords is a major benefit of this form of housing.

Voluntary Affordability in Portland. https://accessorydwellings.org/2014/08/07/do-adus-provide-affordable-housing/

Voluntary Affordability in Edmonton. https://accessorydwellings.org/2017/09/08/garden-suites-in-edmonton-a-private-investment-in-the-public-good/

For example, I have friends who have not raised the rent in 9 years for their upstairs mother-in-law apartment because they love the tenant but she’s on a fixed income. It’s a sweetheart deal they want to last as long as she can handle the stairs. These anecdotes are the rule for homeowners who’ve ‘DIY’ developed an extra unit on their property.

In Portland among owners who live in their ADU, 41% of the primary residences where offered for FREE. Meanwhile, we’re fighting tooth and nail over an inclusionary zoning program that might create 6–10% of new housing as rent restricted. The reality is that a naturally occurring housing type people desperately want to build all over is also 2 1/2 times more likely to create truly affordable housing than our best big policy idea.

2) Making Mother-in-Laws and cottages pencil financially counters wild speculation on McMansions. In the Draft EIS, the City ran different financial models for potential development outcomes. In the draft EIS, 46% of the possible scenarios resulted in tear down/replacement McMansions being the most profitable investment. It was only in cases where the land value was high and the lots were large that adding an ADU and DADU made sense. But if you value the neighborhood and want to curb the momentum of displacement and gentrification, supporting options where a second or third household can add rental income suddenly flips the proforma against the disruptive scourge of McMansions.

3) Renters are Seattle’s majority and any related stigma is out of touch. Owner occupancy restrictions are the biggest impediment to the creation of more housing and keep lower income renters out by limiting the number of options for less expensive dwellings to exist. The checkered history of zoning as a substitute for outlawed racial or class covenants is well documented.

More than 20% of Seattle houses are already rentals. We don’t have a restriction on renting out a detached house and has very few expectations of landlords (more might be in order) yet neighborhoods still thrive. Both tenant and landlord are by and large responsible neighbors. Ask any renter, and they will tell you that they are just as committed as property owners to the neighborhoods, support the local businesses, and participate in civic life. As the majority of Seattleites, renters make up the underlying tax base that funds our government, parks, police, and transit (renters pay property taxes too, just through rent).

4) Besides, owner occupancy restrictions should be illegal. Limiting WHO can use land, as opposed to what the land’s function is isn’t really the job of the land use code. Making property ownership the prerequisite to use is unique to ADUs and has been challenged elsewhere. Other jurisdictions, such as Alberta Canada explicitly allow residency without ownership wherever residences are allowed for that reason.

Find the duplex! (Answer below)

5) Finally, extra dwellings are already everywhere. While people might worry that allowing a ADU and a DADU without owner occupancy restrictions will lead to no less that the ‘destruction of our most unique resource, Seattle’s single family neighborhoods,’ the reality is that there is a long history of small multi-family dwelling coexisting with and even predating the now dominant paradigm of stand alone houses for solitary households. Turn of the last century neighborhoods, like Queen Anne and Wallingford (pictured above), valued for their amenities, walkability, and housing stock, were developed mostly before zoning. They are filled with the highest concentration of small multifamily buildings, house more than 10,000 households, but you might never know it from the street. Honestly that is part of their charm and vitality. If the worst thing is that there are a few more families per street, I think our neighborhoods are more than resilient enough to handle it.

Here is a map of every multifamily building and accessory dwelling in Seattle as off 2016-find the hidden duplex on your street!

Every dot is at least one extra household that doesn’t need a stand alone house.

*In the photo above every structure is a duplex, triplex or fourplex, with the exception of the tallest white structure on the left.

We have been working with a couple who are planning on moving out of the original house, and into a new backyard cottage.  We're pushing the limits within the ordinance--almost exactly 800 square feet--in order to build a 2 bed room, bath and a half cottage. Although the house is small, the spaces inside feel just right.  And we'll be able to include a lot of high finish touches and crisp details because we aren't spending money on lots of square footage. Having a finite perimeter and volume really focuses the mind on the priorities of the design.

The character of the house the client's wanted is very craftsman and the scale and roofline fits right in with the neighborhood in general--certainly not the scary developer vision that opponents of the ordinance summoned during the public hearings.  It reinforces that these projects are for people with a vested interest in both their property and their neighborhood and are very sensitive to the impact on their neighbors.

Here is another view which shows off the walkout patio off the dining space, the entry mudroom and the band of windows that wrap the living room, dining and kitchen:

We are also going to integrate a rain water harvesting system, radiant floors on a super efficient combination boiler, vaulted ceiling upstairs, and a extra height crawlspace with a rat slab to make up for some of the storage space lost in the downsizing.  For floor plans, follow the jump below:

First floor plan:

Second floor plan:

The ordinance  to allow backyard cottages in the other three quarters of Seattle just passed 9-0!  The council's comments focused on the exhaustive community outreach, successful pilot program and benefit of having this housing choice for Seattle. Excellent work by the planning commission, DPD and council.

Usually, the city's process oriented decision making can be cumbersome, and having spent hours in meetings, testifying, and communicating with council, I feel vindicated that our involvement has helped in some small way to bring some innovation to the Single Family zoning.

We're excited to design some of these--in part because of the opportunity to foster multi-generational housing, and the option of building a smaller free standing structure rather than building an addition.  Plus, it is a really fun scale--I think more people will be thinking about bonus studios rather than housing units.

With the impending vote on the backyard cottage ordinance, everyone in the office has been doing a little daydreaming about the DADUs and what they would build.  I have been working on a idea that started with a little ink drawing. It's now developed into a preliminary model/floor plans.  I've flipped the shed roof to have more volume in the shop/studio and worked out the bathroom so that my shop could easily be converted into an open kitchen/living space.

I have also been working out a simple steel structure, clad with structural insulated panels for easy construction and minimization of waste.  The goal is prefabrication of the components offsite, then assemble.

I'd love to try out using a geothermal pre-heating loop, with a hydronic radiant system run of a domestic hot water heater and test the new PV shingles, but that might get a bit expensive.

We're almost there--the committee passed the measure to allow backyard cottages in Seattle.  Next stop will be City Council. There are some notable amendments to the ordinance--the 50 per year allowed cap has been eliminated.  The heights have changed somewhat.  A discussion to limit the cottage height to no more than 15' above the primary residence's roof (which would affect sloped lots primarily) was tabled without conclusion.

The discussion is a little strange, in that some of the requirements being tossed around are more stringent than for building a single family house.  Case in point--if this relative height limit section passes, you will need a topographic survey to prove that the cottage conforms (not required on a new house if well within setbacks and under height), thus added about $2000 to the pricetag for the drawings.  This doesn't make any sense if the city is serious about this as being an affortable option.

Another case in point--Councilmember Rasmussen was leaning toward a neighborhood notice, similar to a MUP, but the neighbor's recourse, provided the cottage design fits the requirements, is nil.  The cottage is a Level 1 decision (no notice necessary, just like a new single family house), but creating such a provision would form a special class of notice ("Here is what is happening next door, but there is nothing you can do about it.  Thanks for coming down.").

Unfortunately, I had to run out before the discussion on the privacy issue, another NIMBY favorite, but in the end the ordinance is one step closer to fruition.

You can see the entire meeting online at the Seattle Channel here.  Backyard Cottage discussion starts at 107.30.

The Planning, Land-Use and Neighborhood Committee is planning on voting on the Backyard Cottages on October 8th.  Last chance to make yourself heard on this issue! It will be a packed agenda, with discussions of the Multi-family code revision as well as the design review process (which will be mandatory in Multi-family).