how much would it cost to add a second story to our approx. 900 sq. ft. home?

Asked by Kj, Seattle, WA Sat May 19, 2012

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Blake Voorhe…, Agent, Seattle, WA
Sat May 19, 2012
Hello KJ - The website "Remodel" provides a cost report for some common remodeling projects in Seattle Washington.

See if any of these provide you some guidance - I linked you straight into the attic remodel:.…

You have read several answers already, so I will refrain from adding details should you have moved on with your needs. If you still have any unanswered questions and care to have an informational telephone conversation with a builder client of mine, I know she would be happy to spend a few minutes with you. She works exclusively on her own properties and projects, and has for well over 10 years, so you need not be concerned about a sales pitch. Instead, she can likely provide you with some initial direction and a rough idea of your cost categories.

Whatever your plans - Good luck!

Blake Voorhees
Coldwell Banker Danforth & Associates
206 718 0703
2 votes
Eggleston Fa…, , 98119
Tue May 22, 2012

Darrell's comment is right on the money. Speaking as an architect, I'd also add that an architect could help you with this process. A good architect should be able to come up with a conceptual strategy for the addition (including consideration of code, structural, and design issues), and give you an opinion of probable construction costs.

AIA Seattle has an excellent online resource for finding a local architect:

And if you're interested in modern design, check out our website:

I hope that helps.
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0 votes
Kj, Home Owner, Seattle, WA
Sat May 19, 2012
Thanks to all. I appreciate the input. -KJ
0 votes
Jirius Isaac, Agent, Kenmore, WA
Sat May 19, 2012
You can see the range of answers you got & in order to know exactly, you will need plans & estimates. Personally, I do not think it is worth the money and hassle. Better, in most cases to just buy another house & turn this one into a rental or sell it. Call me if you want to consult.

Take care, Jirius Isaac
0 votes
Pierre Arcos, Other Pro, Everett, WA
Sat May 19, 2012
Hi Kj,
The best way to get an accurate cost for your 2nd story addition would be to take your plans and specifications to 2 or 3 licensed general contractors. All reputable contractors will give you a FREE estimate for the addition.
Good Luck
0 votes
Ray Akers, Agent, Seattle, WA
Sat May 19, 2012
Adding a 2nd story is a very affordable way to expand your living space. (The most cost-effective way to expand your living space is to finish an unfinished basement.) Since a 2nd story does not involve foundation work, concrete, etc., you should be able to estimate costs in the range of $75 per square foot. If you're adding a master bath, with expensive fixtures, the cost may go higher. BTW, the investments with the best ROI (return on investment) are kitchens, baths, and decks.
0 votes
Gustaf Karlh…, Agent, Seattle, WA
Sat May 19, 2012
I agree with Darrell. Too many factors are unknown for anyone to give a meaningful estimate. There are a couple of different ways to actually construct this depending on the underlying stucture. I am a real estate broker and also an engineer. I have a builder I trust who can give you a good first opinion and cost estimate.
0 votes
Connie Mitch…, Agent, South Padre Island, TX
Sat May 19, 2012
Ball park $100 per sq foot
0 votes
Darrell D. D…, Agent, Schertz, TX
Sat May 19, 2012
The values can very greatly based on requirements. Things to consider as someone who has rehabbed homes are plumbing costs if you plan on adding a bathroom upstairs.....electrical costs if your current sub-panel is older and not sufficient size or style (screw fuses, etc) to support the addition. Structural issues downstairs to support the addition could increase costs. To reduce costs in materials, look at the condition of rafters and ridge beams for re-use of some materials.

I would do you a tremendous disservice by rattling off a price range with so many variables, lack of knowledge of your requirements upstairs (2 bedrooms and a game room, or a bathroom, or you trying to put in a rentable apartment with a kitchen, etc) and lack of current structural, mechanical and electrical component knowledge. I would shop around, get recommendations and definitely get at least 2 or 3 estimates before committing to a contractor. Good luck.
0 votes
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