Home Addition Contractors

A room addition or home extension typically costs $100–$300+ per square foot depending on the type of room, finishes, foundation work, and site conditions. A basic 400 sq ft addition might run $40,000–$80,000; a master suite addition often runs $80,000–$150,000+. GS Construction provides free, detailed estimates.

Most room additions take 8–16 weeks depending on size, permits, weather, and structural work required. Foundation, framing, and roofing are the longest phases. Second-story additions typically take 16–24 weeks.

Yes. We work with licensed architects and structural engineers and handle all village/city zoning, building, electrical, plumbing, and mechanical permits — including Arlington Heights, Palatine, Hoffman Estates, and Schaumburg.

Often, yes. We evaluate the existing foundation and structural framing for capacity, work with an engineer to design proper reinforcement, and coordinate permits. Second-story additions are major projects but add significant square footage without losing yard space.

Absolutely. Our design team specs matching siding, brick, roofing, windows, and trim so the addition reads as part of the original home. Interior transitions are also planned to flow naturally with existing finishes.