discussed individually*
Home Additions
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Runtime:
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Project’s cost:
discussed individually**
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Architectural supervision:
discussed individually
* Depends on the Project
** Price depennds on the style and complexity of the Project.
Your home needs more space. But moving is expensive, disruptive, and means leaving a neighborhood you love. A well-designed home addition gives you the space you need — without leaving.
At DeZZign, we design home additions for clients in Seattle, Bellevue, and Kirkland that feel like they were always part of the original house. Not an afterthought. Not a box attached to a box. A seamless extension of your home, designed from the inside out.
What we design
- Room additions — extra bedrooms, home offices, expanded living areas
- Second story additions — full or partial second floors
- ADUs — detached or attached accessory dwelling units
- Garage conversions — living space, studio, guest suite
- Sunrooms and covered outdoor spaces — year-round living in the PNW climate
Our approach
Every addition starts with the existing house. We study the structure, the style, the materials, the roofline — and design something that extends the logic of what is already there. The addition should look like it was built at the same time as the original home.
We handle the full design process: concept, permit documentation in collaboration with local licensed architects, and construction supervision if needed.
For Seattle Metro Area clients
We are familiar with King County and City of Seattle setback requirements, lot coverage limits, height restrictions, and ADU regulations. We design to code from day one — so your permit process is smooth, not a surprise.
Our portfolio
Stages
Q&A
How do I know if my lot allows an addition?
We check your zoning designation, setback requirements, lot coverage limits, and FAR (floor area ratio) before any design work begins. In most Seattle and Bellevue residential zones, additions are possible — the question is how large and where. We give you a clear answer upfront.
Can you design an ADU on my property?
Yes. We design detached ADUs, attached ADUs, garage conversions, and basement ADUs. Seattle and King County ADU regulations have become significantly more permissive — most single-family lots can now accommodate one or two ADUs. We are current on all requirements.
How long does the permit process take for a home addition?
In Seattle and King County, residential addition permits typically take 3-6 months depending on scope and review backlog. Simple additions may qualify for over-the-counter review. We prepare documentation that minimizes revision requests and moves through the process as efficiently as possible.
Will the addition match my existing house?
That is the goal. We study your existing roofline, siding materials, window proportions, and architectural language before designing anything. The addition should look intentional — not like something added later.
Do you handle the construction as well as the design?
We offer construction supervision as an add-on service. We visit the site regularly, verify that the work matches the approved drawings, and coordinate with contractors on your behalf. If you have your own contractor, we can still provide author supervision.
What does a home addition project typically cost?
Construction costs for home additions in Seattle Metro Area typically range from $300-600 per square foot depending on scope, finishes, and structural complexity. Our design fee is separate and depends on project size. We provide a detailed proposal after the initial consultation and site review.
Contact us
- dezzign.architects@gmail.com
- +380952226547, +14254719496
- Seattle, USA & Kharkiv, Ukraine
- Mon - Sat: 9.00 - 20.00