Home Addition · Bellevue, WA

Home Additions in Bellevue, WA

Bellevue home addition contractor — second-story adds, bump-outs, room additions, and garage conversions. Veteran-owned, licensed, we handle every permit.

Bellevue Home Additions — Growing Your Home, Not Moving

For many Bellevue homeowners, a home addition is a better answer than moving. Bellevue home prices have roughly doubled over the past decade, so adding 400–1,200 square feet to your existing home — often for a fraction of what you'd pay to buy a larger house — is one of the highest-ROI home investments you can make.

But Bellevue home additions are also among the most complex projects a contractor does. You're dealing with setbacks, impervious surface limits, structural engineering, roof tie-ins, HVAC extension, foundation work, and a City of Bellevue permit process that can run 3–6 months before construction can even start.

Purple Heart Pros is a veteran-owned, Washington-licensed general contractor that's done additions across every Bellevue neighborhood: second-story additions in Somerset and Enatai, primary-suite bump-outs in Bridle Trails, garage-to-living-space conversions in West Bellevue, and accessory structures in Newport.

We manage the entire process end-to-end: design coordination, structural engineering, Bellevue permit filing, site prep, foundation, framing, roofing, electrical, plumbing, HVAC, drywall, finish, and final inspection.

What Bellevue Home Additions Typically Cost

Home addition costs in Bellevue vary widely depending on size, complexity (especially whether second-story vs. ground-floor), and finish level:

Bump-out addition (100–250 sq ft, single room): $55K–$140K · Room addition (300–600 sq ft, ground floor): $120K–$280K · Second-story addition (600–1,200 sq ft): $240K–$500K+ · Garage conversion to living space: $70K–$160K

Bellevue additions require structural engineering (typically $3K–$8K separate from construction), site survey, and permit fees (typically $4K–$15K for additions). We itemize these separately in every estimate.

Our Bellevue Home Additions Process

  1. Free in-home consultation. We meet you at the property, walk the scope, and ask the questions that shape a real estimate.
  2. Written line-item estimate. No "approximately" and no allowances without ranges. You see exactly what each trade, material, and line costs.
  3. Scope + fixed-price contract. Change orders are documented, priced, and signed before any extra work proceeds.
  4. Permits & inspections. We pull Bellevue permits directly and coordinate all city inspections through project completion.
  5. Construction. Weekly progress updates, jobsite kept clean, respectful of neighbors and HOAs.
  6. Punch list & walk-through. We fix every item flagged during final walk-through before you sign off.
  7. Warranty. Written craftsmanship warranty on all labor; manufacturer warranties on materials pass directly through to you.

Bellevue Permits, Codes & Local Specifics

Home additions are the most permit-heavy projects we do in Bellevue. City of Bellevue Development Services reviews:

Bellevue's critical area ordinances affect many neighborhoods — steep slope overlays in Somerset and Cougar Mountain, wetlands in parts of Bridle Trails, stream buffers near Lake Washington and Lake Sammamish. If your lot has any of these overlays, we handle the additional environmental review.

Setbacks and impervious surface limits in Bellevue are strictly enforced — your addition design has to respect front, side, and rear setbacks (typically 20, 5, and 20 feet respectively for residential zones) and keep total impervious surface under 35–50% depending on zoning. We design every addition to meet these requirements from day one.

For Bellevue homes in HOAs (Newport Shores, The Lakes, Somerset, Bridle Trails, Vuecrest, Enatai Beach Club), architectural review is also required — typically adding 2–6 weeks to the timeline.

Why Bellevue Homeowners Choose Purple Heart Pros

Bellevue Home Additions FAQ

How much does a home addition cost in Bellevue?

Bellevue home addition costs: bump-outs (100–250 sq ft) $55K–$140K, room additions (300–600 sq ft) $120K–$280K, second-story additions (600–1,200 sq ft) $240K–$500K+, garage conversions $70K–$160K. Structural engineering and permit fees are itemized separately.

How long does a Bellevue home addition take?

Plan on 8–16 weeks of Bellevue permit review before construction can start, plus 4–9 months of construction depending on size. Total project from first call to move-in: 12–18 months for a second-story addition, 8–12 months for a ground-floor addition.

Do I need a structural engineer for a Bellevue addition?

Yes. City of Bellevue requires stamped structural drawings from a Washington-licensed structural engineer for all additions. We work with experienced structural engineers whose fees typically run $3K–$8K for a residential addition. We coordinate this for you.

What are the Bellevue setback requirements for additions?

Standard R-3.5 and R-5 residential zones require 20-foot front setback, 5-foot side setback, and 20-foot rear setback. Lot coverage is capped around 35–50% of the lot size. Steep-slope and critical-area overlays can further restrict. We design every addition within your specific lot's envelope.

Can you add a second story to my Bellevue home?

Yes, when the existing foundation can support it (or we can reinforce it) and setbacks and height limits allow. Second-story additions require careful structural design, roof tie-in, and full HVAC/plumbing/electrical extension. They typically run $240K–$500K+ but can add 30–50% to the home's value in Bellevue.

Will my Bellevue HOA approve a home addition?

Most Bellevue HOAs will approve thoughtfully-designed additions that match the existing home's architecture and respect neighbor sightlines. We've successfully navigated architectural review boards in Newport Shores, The Lakes, Somerset, Bridle Trails, and others. The pre-submission consultation with your HOA is critical — we help prepare that package.

Ready to Start Your Bellevue Home Additions?

Free estimate, same-day response, no runaround.

Call (425) 565-4795 Get a Free Quote