More house. Same lot.
Single-room expansions, second-story additions, sunrooms, and in-law suites — engineered, permitted, and built to current Connecticut code. Across Hartford and Tolland Counties.
A custom home addition can be cheaper than relocating.
You like your neighborhood, your school district, your commute. You don't want to leave. You just need more square footage. A well-designed home addition gives you the space you need — and adds 70-80% of its cost back to your home's resale value.
Whether it's a master suite expansion, a mudroom-and-laundry combo, a second floor, or a full attached ADU, Lagace handles it all in-house: design, engineering, permits, framing, mechanicals, finishes.
- Single-story rooms — kitchens, family rooms, sunrooms, master suites
- Second-floor additions and dormer expansions
- In-law suite and ADU additions (CT 2026 ADU rules apply)
- Garage-with-living-space-above builds
- Engineering, permits, and town inspections handled for you
Every kind of expansion.
Single-Story Additions
Family rooms, master suites, mudrooms, sunrooms — added onto your existing footprint with seamless rooflines.
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Second-Floor Additions
Add a full second story or partial dormer. Engineered for your existing foundation. Doubles your square footage without expanding the lot.
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In-Law Suites & ADUs
Connecticut's 2026 ADU rules opened the door for accessory dwelling units. We design, permit, and build them — attached or detached.
Learn more →2026 Connecticut addition pricing.
Costs vary by size, foundation type, and finish level. Every addition gets a written estimate.
Single-Room Bump-Out
$45K – $90K
200-400 sq ft addition. Ideal for expanded kitchen, mudroom, or master closet.
- New foundation slab or extension
- Roof tie-in & matching siding
- Insulation, drywall, finish
Family-Room or Master Suite
$95K – $180K
400-800 sq ft addition with new mechanicals. The most-requested addition we build.
- New full bath if included
- HVAC zone extension
- Hardwood or LVP floors
- Permit + engineering package
Second-Floor or ADU
$200K – $400K+
Full second story or detached ADU. Significant structural and mechanical scope.
- Foundation reinforcement
- Full electrical panel upgrade
- Engineered drawings
- Town zoning coordination
Design through certificate of occupancy.
Site Visit
We walk your property, look at existing footprint, lot setbacks, and what you actually need.
Design & Engineering
Architectural drawings, structural engineering, and a written estimate.
Permits
We submit drawings to your town, attend zoning meetings if needed, and pull all required permits.
Build
Foundation, framing, mechanicals, drywall, finish — same Lagace crew throughout.
CO & Hand-Off
Final inspection, certificate of occupancy, walk-through. You move in.
Book a free, no-pressure quote.
Free on-site visit. We'll talk through what you need, your lot constraints, and rough costs — then follow up with a written estimate.
- On-site consultation, no obligation
- Line-itemized written estimate
- Real timelines and a real start date
- CT Licensed & Insured (Reg. HIC.0617594)
Tell us about your project. We'll call you back within 1 business day.
Skip the back-and-forth. Book a meeting directly on Scott's calendar.
Prefer to call? Reach Scott directly at (860) 933-2700 • CT Licensed & Insured (Reg. HIC.0617594)
Hartford & Tolland Counties
Based in Andover, CT — building, remodeling, and adding on to homes across central and eastern Connecticut for over two decades.
Ready to add the space you actually need?
Whether it's a single room, a second story, or a full in-law suite — we design, engineer, and build it.
CALL DIRECT(860) 933-2700