Home Addition Contractor in Vancouver, WA
I See Construct builds room additions, second-story additions, and garage-to-living-space conversions for homeowners across Vancouver, WA, Battle Ground, and Clark County. Home additions in Southwest Washington typically cost between $80,000 and $200,000 depending on the square footage being added and the complexity of tying into the existing structure. We manage the design coordination, permit applications, and all construction work as a single crew.
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At a Glance
$80,000 to $200,000+ depending on addition size, type, and structural complexity
4 to 10 months from contract to final inspection including permitting
Types of Additions and Conversions We Build
Room Additions
A room addition expands the footprint of the existing home by extending an exterior wall or adding a new structure connected to the home. Common room additions in Clark County include primary bedroom suites, family rooms, home offices, and sunrooms. We tie into the existing foundation, frame, roofline, and siding so the addition blends with the original structure.
Second-Story Additions
Adding a second story is a cost-effective way to significantly increase the living area of a one-story home without expanding the footprint into the yard. Second-story additions require a structural assessment of the existing foundation and first-floor framing before design can begin. We work with structural engineers as needed and manage the entire process.
Garage Conversions
Garage conversions repurpose an attached or detached garage into a finished living space, home office, gym, or ADU. This involves insulating the walls and ceiling, adding flooring, relocating or adding HVAC, and installing windows and doors. Garage conversions in Vancouver and Battle Ground are a cost-effective alternative to building a new room addition.
Home Addition Costs in Vancouver, WA
Single-room addition (300 to 500 sq ft):
$80,000 to $130,000
Master bedroom suite addition:
$90,000 to $150,000
Second-story addition (full floor):
$150,000 to $250,000+
Garage conversion to living space:
$50,000 to $90,000 depending on scope
Sunroom or three-season addition:
$50,000 to $100,000
Permitting Home Additions in Clark County
Every home addition in Clark County and the City of Vancouver requires a building permit. The application includes site plans, floor plans, structural drawings, and energy compliance documentation. Clark County also reviews additions for setback compliance, lot coverage, and impervious surface limits. The plan review period currently runs 4 to 12 weeks.
We prepare all permit documents, submit the application, and respond to any plan review comments. Inspections are scheduled through Clark County or the city as work progresses, including footing, framing, insulation, and final inspections.
How We Approach Addition Projects
We do not use subcontractors without your knowledge. Our own crew handles framing, roofing tie-in, windows, insulation, drywall, and interior finishes. Mechanical trades (electrical, plumbing, HVAC) are coordinated with licensed sub-contractors we have worked with consistently across Clark County.
The first step is an on-site assessment to review the existing structure, discuss your goals, and identify any constraints like setback limits, utility locations, or structural issues in the existing home. We then provide a written estimate broken down by phase so you have full visibility into the project cost.
Frequently Asked Questions
Home addition costs in Vancouver, WA and Clark County typically range from $80,000 to $200,000 or more depending on the size and type of addition. A single-room addition of 300 to 500 sq ft generally runs $80,000 to $130,000. Second-story additions and larger suite additions are at the higher end. We provide detailed estimates after reviewing the project scope and existing home.
Yes. Every room addition in Clark County and the City of Vancouver requires a building permit. This includes garage conversions that create new habitable square footage. Permits are required for structural, mechanical, electrical, and plumbing work involved in the addition. We manage the full permit process.
A single-room addition of 300 to 500 sq ft typically takes 4 to 6 months from contract to final inspection. This includes 4 to 12 weeks for permit review and 8 to 16 weeks of construction. Second-story additions run 6 to 10 months. Garage conversions without structural changes can sometimes be completed in 2 to 3 months.
A home addition expands the square footage of the primary living area and is connected to and part of the main home. An ADU is a self-contained secondary dwelling unit with its own kitchen, bathroom, and entrance. Some attached ADUs are built as additions, but they are permitted under ADU regulations. We build both and can help you determine which approach fits your goals and lot.
Yes. Garage conversions are one of the most common projects we complete in Vancouver and Clark County. We convert attached garages into finished home offices, bedrooms, playrooms, and ADUs. The work includes insulation, flooring, HVAC, windows, electrical, and finishes. A building permit is required for all habitable conversions.
Ready to Add Space?
Tell us what you are working with. We come out, look at the property, and give you a straight answer on what is possible and what it costs.