Home Addition Cost Calculator & Estimator (2026)
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Estimate No. RA-20260823-11213
Home addition estimate
A complete budget for a 200 sq ft home addition in ZIP code 11213, with mid-range finishes. The categories and amounts below come from the provided project data.
A detailed planning budget organized by professional services and project purchases.
- ZIP code
- 11213
- Country
- USA
- Renovation
- Home addition
- Finish quality
- Mid-range
- Area
- 200 sq ft
Detailed cost breakdown
The full budget is organized into professional services and purchases. Expand or collapse either section to review every category and its scope.
Professionals · 18 categories$24,090
Labor, design, construction, installation, and project-management services.
| Category | Scope | Cost |
|---|---|---|
| Fees, profit and overhead | Cover contractor fees, project management, and overhead costs associated with managing the home addition project. | $3,410 |
| Carpentry and framing | Perform structural framing for the new addition, including walls, roof, and any necessary custom carpentry for built-ins or unique architectural features. | $2,885 |
| Siding and exterior | Install new siding on the exterior of the addition to match the existing home, ensuring weatherproofing and aesthetic consistency. | $1,945 |
| Roofing | Install new roofing materials to cover the addition, ensuring it matches the existing roof in style and material. | $1,935 |
| Electrical | Install new electrical wiring, outlets, and lighting fixtures in the addition to ensure functionality and compliance with electrical codes. | $1,890 |
| Architect | Engage an architect to design the addition, ensuring it integrates seamlessly with the existing structure and meets local building codes. | $1,460 |
| Drywall and insulation | Install and finish drywall in the addition, along with necessary insulation to ensure energy efficiency. | $1,415 |
| Plumbing | Install new plumbing lines to service the kitchenette in the addition, ensuring proper water supply and drainage. | $1,195 |
| Window and door installation | Install new windows and doors in the addition, ensuring proper fit and insulation. | $980 |
| Countertop | Install a countertop in the kitchenette area of the addition, using mid-range materials for durability and style. | $965 |
| Flooring | Install new mid-range flooring in the addition, suitable for a residential space. | $945 |
| Mechanical | Service existing mechanical systems to integrate with the new addition, including HVAC and plumbing adjustments. | $920 |
| Painting | Paint the interior walls, ceilings, and trim of the addition, using mid-range paint for durability and aesthetic appeal. | $905 |
| Designer | Engage a designer to assist with interior layout and finish selections for the addition, ensuring aesthetic coherence with the existing home. | $880 |
| Thermal, moisture and air sealing | Ensure the addition is properly sealed against thermal, moisture, and air infiltration, using appropriate sealing materials and techniques. | $715 |
| Finish and trim | Install finish and trim work in the addition, including baseboards, crown molding, and other decorative elements. | $690 |
| Tile installation | Install tiles in the kitchenette area of the addition, ensuring proper setting and alignment. | $485 |
| Demolition | Perform necessary demolition to prepare the site for the new addition, including removal of any existing structures or landscaping. | $470 |
Purchases · 11 categories$11,215
Materials, fixtures, equipment, furnishings, permits, and other project purchases.
| Category | Scope | Cost |
|---|---|---|
| Building materials | Purchase materials for constructing the addition, including lumber for framing, drywall, insulation, and mid-range flooring materials. Also includes paint for walls and ceilings. | $3,060 |
| Cabinetry and built-ins | Install new cabinetry in the additional space, including a small kitchenette with mid-range cabinets and a built-in closet for storage, sized for a 200 sqft area. | $1,890 |
| HVAC equipment | Install a new HVAC system or extend the existing system to accommodate the additional space, including ductwork and a thermostat. | $1,340 |
| Doors and windows | Purchase and install new windows and doors for the addition, ensuring they match the existing home's style and provide adequate insulation. | $1,175 |
| Furnishing | Purchase furnishings for the addition, including basic furniture and decor to complement the new space. | $1,095 |
| Lighting | Install new lighting fixtures and switches in the addition, ensuring adequate illumination and style consistency with the existing home. | $585 |
| Tiles and stones | Install tile flooring or backsplash in the kitchenette area of the addition, using mid-range tiles. | $560 |
| Plumbing fixtures | Install plumbing fixtures in the addition, including a sink and faucet for the kitchenette. | $545 |
| Permits | Obtain necessary permits and inspections for the construction of the addition, ensuring compliance with local regulations. | $410 |
| Miscellaneous | Cover any additional materials or unexpected costs that may arise during the construction of the addition. | $365 |
| Hardware and fasteners | Purchase and install necessary hardware and fasteners for the addition, including door handles, cabinet hardware, and construction fasteners. | $190 |
Analysis and assumptions
This provided budget includes professional services and purchases for the stated location, area, renovation type, and mid-range finish quality. Actual costs can vary with site conditions, selections, taxes, and changes to scope.
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COST BY ADDITION TYPESTypical 2026 costs by addition type
Average structural investment ranges by project type and finish tier
| Addition Type | Low Tier | Mid Tier | High Tier |
|---|---|---|---|
| Bedroom Addition | $40,000 | $90,000 | $180,000 |
| Bathroom Addition | $25,000 | $60,000 | $130,000 |
| Sunroom / Enclosed Porch | $20,000 | $45,000 | $100,000 |
| Second Story Addition | $100,000 | $200,000 | $400,000+ |
| Garage Conversion | $15,000 | $35,000 | $75,000 |
*Note: Cost models are subject to regional labor variations, zoning restrictions, and site conditions. Low tier assumes basic materials and standard layouts; mid tier reflects upgraded fixtures and semi-custom engineering; high tier features premium architectural details and complex structural integration.
COST BY SQFTRoom Addition Cost Per Square Foot
When planning a layout extension, calculating your baseline home addition cost per square foot helps set a realistic starting budget. On average, a structural addition runs anywhere from $150 to $450+ per square foot depending on the architectural complexity, utility requirements, and selections.
| Addition Style | Low Tier | Mid Tier | High / Luxury |
|---|---|---|---|
| Standard Room / Bedroom | $150 – $200 / sq ft | $200 – $320 / sq ft | $320 – $450+ / sq ft |
| Bathroom Addition | $250 – $350 / sq ft | $350 – $500 / sq ft | $500 – $750+ / sq ft |
| Sunroom / Enclosed Porch | $125 – $175 / sq ft | $175 – $275 / sq ft | $275 – $400+ / sq ft |
| Second Story Bump-Up | $200 – $275 / sq ft | $275 – $400 / sq ft | $400 – $600+ / sq ft |
DECOND STORY HOME ADDITION
Second Story Addition Cost Calculator
Building up instead of out is an excellent way to double your square footage without sacrificing valuable yard space. However, utilizing a second story addition cost calculator involves tracking hidden structural elements that standard ground-level expansions completely bypass.
On average, adding a full second level costs between $200 and $400 per square foot, totaling roughly $100,000 to $400,000+. When evaluating a vertical "bump-up" project, your calculator matrix should account for these three specific vertical cost drivers:
HOW IT WORKS
How does Remodelum’s Estimator and Calculator work?
TYPES OF RENOVATIONS COVEREDOther Renovation Types covered by Remodelum
Whole House
Whole House Renovation Cost Estimator
Room-by-room estimate for complete home renovations, by ZIP code.
Kitchen
Kitchen Remodel Cost Estimator
Cabinets, countertops, appliances, and labor costs by ZIP code.
Bathroom
Bathroom Remodel Cost Estimator
Half bath, full bath, and master bath cost breakdowns.
Patio
Patio Renovation Cost Estimator
Pavers, concrete, pergolas, and outdoor living spaces.
Basement
Basement Finishing Cost Estimator
Finishing, refinishing, improvement and basement conversion costs.
REMODEL BUDGET TRACKER
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FAQs
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Room additions typically range from $120 to $250 per square foot, depending on location and materials.
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Yes, second-story additions cost more—usually $200 to $400 per square foot—due to structural engineering and roofing modifications.
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asic single-room additions with minimal plumbing and finishes are usually the most cost-effective.
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Yes, most jurisdictions require building permits for room or home additions. Your contractor should factor this into your estimate.
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Second-story additions often require structural reinforcements and cost more per square foot. Use the calculator to compare both scenarios instantly.
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Yes, Remodelum supports different room types, including sunrooms, garages, and master suites.
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Yes. You can estimate costs without signing up. Optionally, create a free account to save and compare estimates.