Kirkland homeowners frequently ask: what does it cost to add on to my home? Here is a realistic breakdown of home addition costs specific to the Kirkland, WA market in 2026.
Home Addition Costs in Kirkland (2026)
| Addition Type | Cost Range |
|---|---|
| Primary suite addition (400 sq ft) | $160,000 – $270,000 |
| Second story addition (full floor) | $330,000 – $580,000 |
| Kitchen addition (250 sq ft) | $110,000 – $190,000 |
| Home office addition (200 sq ft) | $85,000 – $155,000 |
| Family room addition (300 sq ft) | $120,000 – $200,000 |
| Garage conversion ADU | $90,000 – $175,000 |
Architect Fees for Kirkland Additions
- Small addition (under 400 sq ft): $16,000-$28,000
- Medium addition (400-800 sq ft): $22,000-$42,000
- Full second story: $35,000-$65,000
Kirkland vs. Seattle Costs
Construction costs in Kirkland are typically 5-10% lower than Seattle for comparable projects, due to lower labor staging costs and easier site access. Permit fees are also lower. Combined with Kirkland’s faster permit review, the total project cost and timeline advantage over Seattle is meaningful.
Get a Free Cost Estimate
Piper Cole Architects provides detailed cost estimates in free initial consultations. We are headquartered in Kirkland and work throughout the Eastside. Contact us — call 425-753-6452.