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Estimate the cost of a new addition by ZIP and square footage — foundation, framing, mechanicals, and finishes — with an AI breakdown.
Addition
Foundation type sets the floor price
Crawlspace, slab, or full basement under your addition can swing the budget by $20–60k.
Tying into existing systems
Extending HVAC, plumbing, and electrical from the existing house is rarely as simple as it looks.
Roofline complexity
Matching the existing roof pitch and tying in cleanly costs more than a plain shed roof — but it's worth it for resale.
Save this estimate, turn it into an editable scope of work, and get a free AI review of any contractor contract — we flag missing clauses against your state's requirements.
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