Room Addition Cost
Room additions add permanent square footage and can transform a home's livability. Costs include foundation, framing, roofing, exterior finishing, HVAC, electrical, and interior finishing.
Low Estimate
$35,000
Mid-Range
$90,000
High End
$200,000
Avg ROI
55%
Interactive Cost Estimator
Mid-grade materials, good quality fixtures, standard options.
Estimated Total Cost
$90,000
Based on 200 sq ft at mid quality. Actual costs vary by location and contractor.
Cost Breakdown
Approx. $45,000 at mid-range pricing
Approx. $45,000 at mid-range pricing
Labor-heavy projects (with high labor costs) benefit most from getting multiple contractor bids. You can save on materials-heavy projects by sourcing materials yourself at contractor pricing.
What Affects the Price
- 1Square footage
- 2Foundation type
- 3Number of stories
- 4Roof integration
- 5HVAC, plumbing, electrical extension
Popular Upgrades
- Cathedral ceiling
- En-suite bathroom
- Walk-in closet
Discuss upgrades with your contractor before finalizing the quote. Some upgrades are cheaper to include during initial construction than to add later.
DIY vs. Hire a Pro
Professional installation strongly recommended.
DIY Advantages
- • Save 50% on labor costs ($45,000 at mid-range)
- • Control over timeline and material selection
- • Satisfaction of completing the project yourself
- • Flexibility to work in phases
Pro Advantages
- • Guaranteed workmanship and professional finish
- • Proper permits and code compliance
- • Access to trade pricing on materials
- • Required for safety and code compliance
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