In-Law Suites in Massachusetts covers the full scope from initial consultation through commissioning. MA passed ADU law 2024. Growing demand. Pro Build is a Massachusetts-licensed contractor with the trade licenses for construction & remodeling work in-house — we file every required permit, schedule the inspection, and stand behind the work with a 5-year workmanship guarantee on installation labor.
How Much Does In-Law Suites Cost in Massachusetts?
In-Law Suites pricing in Massachusetts varies by project scope, materials, and home characteristics. We deliver line-item estimates within 24 hours of on-site visit so you see exactly where your money goes.
Pricing depends on scope, materials, and timeline. We deliver a free written estimate within 24 hours of an on-site visit — line-item breakdown so you see exactly what you're paying for. No high-pressure sales tactics.
Calculate Your Exact In-Law Suites Cost
Free on-site visit + line-item written estimate within 24 hours. No commitment.
What Makes In-Law Suites Different in Massachusetts
Massachusetts has the most demanding HIC, code, and permit landscape for residential construction in the country. In-Law Suites requires a Massachusetts Construction Supervisor License (CSL), MA HIC registration, and 780 CMR-compliant scope. Pre-1978 homes layer EPA RRP lead-safe handling on top.
- MA Construction Supervisor License required for permit pull on most {name_lower} scope
- MA HIC registration required for any contract over $1,000 (MGL c. 142A)
- Maximum 1/3 deposit + milestone payments protected by HIC law
- 780 CMR Massachusetts state building code enforced statewide
- Specialized Stretch Code in 14 municipalities adds energy/electrification requirements
- Pre-1978 EPA RRP lead-safe protocols on every applicable project
Not Sure Which In-Law Suites Approach Fits Your Home?
Free Manual J / load calculation + system recommendation + exact pricing within 24 hours.
Brands We Install for In-Law Suites
Equipment selection drives long-term performance more than any other variable. We install only manufacturer-certified equipment with proven track records and Massachusetts service networks. Off-brand stock from big-box stores typically voids manufacturer warranties on installation defects — Pro Build sources only through authorized distributors.
- Andersen 400 Series + A-Series windows
- Pella Architect Series, Lifestyle, Impervia
- Marvin Elevate, Signature Ultimate windows
- Therma-Tru Fiberglass entry doors
- James Hardie HZ5 fiber cement siding
- CertainTeed Vinyl siding, Cedar Impressions
- GAF Timberline HDZ architectural shingles
- Owens Corning TruDefinition Duration shingles
Will Your Massachusetts Home Need Mass Save Insulation First?
Major construction is the right window to upgrade insulation while walls or attics are open. Mass Save covers 75–100% of insulation cost, compounding the value of the project.
We coordinate the mass save insulation and in-law suites as one project under one project manager — single permit pull, single warranty, single point of accountability. Mass Save Insulation Quote →
Massachusetts Permits, Codes, and the Specialized Stretch Code
Every in-law suites project in Massachusetts requires a 780 CMR building permit filed under a licensed contractor. Pre-1978 homes require EPA RRP lead-safe procedures. Pre-1981 homes may require asbestos screening before any envelope work. We file permits under our license — the homeowner pulls nothing and signs no permit applications.
For the 14 Massachusetts municipalities under the Specialized Stretch Code, additional energy and electrification requirements apply on new construction and major renovations. We design every project for full Stretch Code compliance from day one — confirmed against current Mass DOER guidance and the latest Massachusetts Climate Roadmap Act amendments.
Our 6-Step In-Law Suites Process
Every Pro Build project follows the same six-step framework — designed for transparency, code compliance, and consistent outcomes.
- Free on-site consultation. A Lead Construction Supervisor walks the project, measures, photographs, and identifies cross-trade dependencies. No commitment.
- Written estimate within 24 hours. Line-item breakdown. Materials, labor, permits, timeline. Mass Save rebate calculated where applicable.
- Permit filing. 780 CMR mechanical/electrical/plumbing/structural permits filed under our license. Pre-1978 homes get EPA RRP lead-safe handling.
- Project kickoff. Single project manager assigned. Schedule confirmed. Materials ordered. Pre-construction homeowner walkthrough.
- Installation / construction. Daily site cleanup. Homeowner communication via single PM. Change orders documented in writing per MA HIC law.
- Final walkthrough + warranty registration. Manufacturer warranties registered on your behalf. Pro Build 5-year workmanship guarantee activated. Final inspection cleared.
Skip the Generic Contractor Quote Game
5-min reply. Massachusetts Licensed. Permits filed. In-Law Suites done right, the first time.
How to Identify a Qualified Massachusetts In-Law Suites Contractor
Massachusetts contractor licensing is more strict than most states. Verify all of the following before signing anything — checking just one is not enough:
- MA Construction Supervisor License + HIC Registration
- Massachusetts requires the CSL for any project requiring a building permit, plus MA HIC registration for any contract over $1,000. Verify both on the MA Department of Public Safety database before scheduling.
- MA HIC Registration (for any contract over $1,000)
- Required by MGL c. 142A. The HIC number must appear on every contract and proposal. Not optional.
- Written line-item estimate within 24 hours
- A reputable Massachusetts contractor delivers a line-item written estimate after an on-site visit. Contractors quoting from a phone call or refusing to itemize materials and labor are a red flag.
- Permit-pulling contractor — not the homeowner
- If a contractor asks the homeowner to pull the permit, they are unlicensed for that scope. Walk away. The contractor must pull the permit under their license.
- Active manufacturer-authorized status
- Manufacturer warranties on installation defects require authorized installer status. Off-brand stock or unauthorized installation often voids the manufacturer warranty entirely.
- MA HIC arbitration eligibility
- HIC-registered contractors are bound by the MA HIC arbitration program — homeowner protection of last resort. Unregistered contractors offer no such recourse.
Massachusetts In-Law Suites Case Study
Our 4-Layer Warranty
Every Pro Build in-law suites project is backed by four layers of coverage:
- Manufacturer warranty
- Full coverage on all installed equipment and materials. Registered on your behalf within 14 days of project completion.
- Pro Build workmanship guarantee
- 5 years on installation labor. We return at no cost if anything we installed needs adjustment within the warranty period.
- Massachusetts code compliance
- All work passes 780 CMR Massachusetts code inspection. We file every required permit and schedule the inspection. If anything fails inspection due to our work, we fix it and re-inspect at no charge.
- Massachusetts HIC compliance
- Every project governed by an MA HIC-compliant written contract per MGL c. 142A. Maximum 1/3 deposit, milestone payments, 3-day right of rescission. MA HIC arbitration program available.
Why Massachusetts Homeowners Choose Pro Build for In-Law Suites
Most Massachusetts contractors specialize narrowly and subcontract anything outside their lane — losing accountability at every handoff. Pro Build holds every relevant trade license in-house: Construction Supervisor, Master Electrician, Master Plumber, Master Gas Fitter, EPA 608 Universal, EPA RRP, Mass Save HPC, BPI. The same Lead Construction Supervisor who scopes your in-law suites also coordinates the cross-trade work that compounds the value.
- One project, one PM, one warranty. Cross-trade coordination under one contract — no homeowner managing four contractors.
- Free written estimate within 24 hours. On-site visit, line-item breakdown, no high-pressure sales tactic.
- 5-min response during business hours. Faster than industry standard by 5×. We pick up.
- Income-eligible specialty. Mass Save income-eligible filing routinely brings net cost to $0 on standard installs.
- Same-day Manual J / load-cal where applicable. Most contractors guess capacity. We measure.
- Permits filed, inspections scheduled. The homeowner signs nothing at the building department.
Cross-Trade Coordination That Saves You Time
Most in-law suites projects in Massachusetts depend on or trigger work in adjacent trades. We hold every relevant license in-house so your project doesn't bounce between contractors:
- Panel Upgrades — coordinated with this project as one scope under one project manager.
- Repiping Services — coordinated with this project as one scope under one project manager.
- Hvac — coordinated with this project as one scope under one project manager.
- Mass Save Insulation — coordinated with this project as one scope under one project manager.