Instead of braving a competitive market to buy a new home to meet the needs of a growing family, many are instead opting to upgrade their current home.

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Q: My family has outgrown our current home, but we can’t afford to buy a new one. How do we add the space we need to our existing house?

A: Seattle’s surging home prices are no secret — the median home price is more than $700,000! Instead of braving this competitive market to buy a new home to meet the needs of a growing family, many are instead opting to upgrade their current home.

Here are a few ways to attain that extra space you may need.


Sometimes a little extra space can make a big impact. One way to gain square footage is to do what’s called a bump-out, which is a small addition (as opposed to a full addition) created to expand an existing room. Many people choose to expand their kitchens this way, but you can also bump out bathrooms, bedrooms and laundry rooms.

Finished basements

Many homes have unfinished basements just waiting for their potential to be tapped.

If your basement is finished but not serving your current needs, consider a remodel. A chopped-up basement can be reconfigured to create a den or playroom, while an open space can be divided into rooms for extra storage or added privacy.

A basement can also be transformed into an accessory dwelling unit, or ADU — just add a bathroom, kitchenette and separate entrance, and make sure it meets local building codes.


One of the most popular ways to add square footage is with a full addition. There are a variety of options that fit any home’s footprint and logistics. Build up, out or even down — all will add to your square footage and your home’s value.

Accessory dwelling units

An ADU is a second living unit that exists on the same property as an existing single-family home. Both attached and detached (DADU) units are rising in popularity in Seattle, especially given the city’s proposal to loosen the current regulations.

ADUs can be wonderful additions to your property while also boosting value, providing an income stream or housing a loved one.

So how much will this cost? The short answer — and the one you will likely hear from any designer or builder — is, “It depends.” Be wary of anyone quoting you a price without plans and a list of design choices.

Here are a few factors that affect construction costs for any of these projects:

Finishes. Carrara marble shipped in from Italy or granite from a local supplier?

Size of space. 50-square-foot bump-out or 800-square-foot ADU?

Existing site conditions. Some sites are simply more challenging than others to build on, requiring more work and more money.

ADUs, though small in size, are often not as small in price. Construction costs are based on a number of variables, but they typically start at $250,000, plus permitting fees often totaling $4,000 to $6,000.

Also, figure in 8–15 percent of construction costs for architecture and engineering. Even if the project seems small, nothing can be built without a set of plans. Try asking your friends, family or coworkers for recommendations, or a general contractor for a referral. The latter can match you with someone who has already been vetted and is appropriate for the scope of your project.

If you choose to move forward with any of these home upgrades, be sure to hire both a general contractor and an architect at the start of your project. Having both on the team from the beginning will make the process go smoother and typically save you both time and money.


Laura Grange is the marketing and communications manager of Hammer & Hand and a member of the Master Builders Association of King and Snohomish Counties, and HomeWork is the group’s weekly column. If you have a home improvement, remodeling or residential homebuilding question you’d like answered by one of the MBA’s more than 2,800 members, write to