permits.llc

Middlesex County, Massachusetts

Lexington, MA Building Department and Permits

Building Office

Hours
Mon/Wed/Thu 8:30-4:30; Tue 8:30-7:00; Fri 8:30-1:00
Inspector of Buildings
Jim Kelly, Building Commissioner

Verified 2026-09-16 against the official Lexington website.

Do I need a permit in Lexington, and who pulls it?

In Massachusetts, most permits are pulled by the licensed contractor doing the work, not the homeowner. For one- and two-family homes the state building code requires a licensed construction supervisor or a registered design professional to oversee construction, and for existing owner-occupied one- to four-family homes the contractor must also be registered with the Home Improvement Contractor program.

The homeowner exception is narrow. The building code lets an owner-occupant of a one- or two-family home apply for a building permit for work on their own home, but it applies to building permits only: electrical work may only be done by a master or journeyman electrician licensed by the state, and plumbing and gas work only by a licensed plumber or gas fitter, each under a permit issued to that licensee. It also has a cost the state warns about directly: a homeowner who pulls the building permit themselves may not be eligible for the Guaranty Fund if the contractor's work goes wrong.

Need a licensed contractor? See HVAC, roofing and other contractors serving Lexington on Mass Home Comfort.

Sources: When is a Construction Supervisor License required?; Massachusetts State Building Code, 780 CMR; HIC Homeowner Resources; Electricians consumer fact sheet; Plumbers and gas fitters consumer fact sheet.

Heating and cooling in LexingtonReplacing a furnace, boiler, water heater or central air conditioner, or installing a heat pump or ductless mini split, is licensed work in Massachusetts. Anything on the gas side, a gas furnace, boiler, water heater or range connection, is gas fitting, and the state issues gas-fitting permits only to a licensed plumber or gas fitter.Read more

The electrical side of a heat pump, mini split or AC condenser needs an electrical permit pulled by a licensed electrician. Your Lexington building department may also require a mechanical permit for the equipment itself; the contractor pulls that too.

Heating and cooling installers are one of the trades mass.gov specifically exempts from Home Improvement Contractor registration, so do not expect an HIC number from an HVAC company. What you should expect is a gas-fitter or plumber licence for gas equipment and an electrician's licence for the wiring, with a permit on file for each.

If you are counting on a Mass Save rebate for a heat pump, the equipment must be installed by a contractor participating in the Mass Save Heat Pump Installer Network. A permit trail is part of how that work is documented, so an unlicensed, unpermitted install can cost you the rebate as well as the inspection.

Sources: Plumbers and gas fitters consumer fact sheet; Electricians consumer fact sheet; HIC Homeowner Resources; Air source heat pump rebates.

Full Massachusetts guide
Windows and doors in LexingtonReplacing windows or exterior doors is not on the list of work the Massachusetts building code exempts from a permit, so plan on one. The code's own exemption for "ordinary repairs" does not cover anything that removes or changes a required means of egress, which is exactly what a bedroom window is, and changing the size of an opening is an alteration to the structure.Read more

Whether a strict like-for-like swap in the same opening counts as an ordinary repair is a call the Lexington building department makes, so ask before assuming.

In an existing owner-occupied one- to four-family home, the contractor who replaces your windows or doors must be registered as a Home Improvement Contractor, and the state's guidance is that the registered contractor pulls the building permit. A written contract is required by law for any home improvement job over $1,000, and the contractor may not collect more than one-third of the price up front.

If Lexington has a local historic district, exterior window and door changes there usually need the historic district commission's approval before the building permit issues. That is a town rule, not the state code, so check with the building department.

Sources: Massachusetts State Building Code, 780 CMR; HIC Homeowner Resources; When is a Construction Supervisor License required?.

Full Massachusetts guide
Roofing in LexingtonRe-roofing and roof replacement are not among the projects the Massachusetts building code exempts from a permit, so in Lexington treat a roof job as permitted work. Because the work touches the building's structure and weather envelope, it is overseen by a licensed construction supervisor, and on an existing owner-occupied one- to four-family home the roofing contractor must also hold Home Improvement Contractor registration.Read more

The state's guidance is that the registered contractor applies for the permit, not you.

The building code has specific requirements for roof coverings, underlayment and ice protection that the inspector checks against, and they depend on the roof type and the edition of the code in force. Rather than quote them here, ask the Lexington building department what it inspects for on a re-roof; the contractor pulling the permit is expected to know.

Sources: Massachusetts State Building Code, 780 CMR; When is a Construction Supervisor License required?; HIC Homeowner Resources.

Full Massachusetts guide
Siding in LexingtonResiding a house is not on the list of work the Massachusetts building code exempts from a permit, so in Lexington plan on a building permit for siding replacement. The code's "ordinary repairs" exemption is meant for patching what is there, not stripping and recladding the envelope, and the Lexington building department decides where that line falls; the contractor pulling the permit is expected to ask.Read more

On an existing owner-occupied one- to four-family home the siding contractor must be registered as a Home Improvement Contractor, and the state's guidance is that the registered contractor applies for the permit rather than the homeowner. A written contract is required by law for any home improvement job over $1,000, with no more than one-third of the price collected up front.

If Lexington has a local historic district, a change of siding material or profile on a building inside it usually needs the historic district commission's approval before the building permit issues. That is a town rule, not the state code, so check with the building department.

Sources: Massachusetts State Building Code, 780 CMR; HIC Homeowner Resources; When is a Construction Supervisor License required?.

Full Massachusetts guide

Recent building permits in Lexington

2,007 permits on file across 19 months. Records through July 31, 2026.

Last 90 days: 55 building, 4 plumbing.

Permits commonly pulled in Lexington over the last twelve months: 972 building, 72 plumbing, 12 demolition, 4 electrical and 2 gas permits.

Most recent building permits filed in Lexington, Massachusetts
FiledStreetType
Jul 31, 2026LINMOOR TERBuilding
Jul 31, 2026BEDFORD STBuilding
Jul 31, 2026SHERBURNE RDBuilding
Jul 30, 2026BERTWELL RDBuilding
Jul 30, 2026SPRING STBuilding
Jul 30, 2026WORTHEN RDBuilding
Jul 30, 2026ELDRED STBuilding
Jul 29, 2026EFFIE PLBuilding
Jul 29, 2026LINCOLN STBuilding
Jul 29, 2026CONESTOGA RDBuilding
Jul 29, 2026CLEMATIS RDPlumbing
Jul 29, 2026EMERSON GARDENS RDBuilding
Jul 29, 2026BEDFORD STBuilding
Jul 29, 2026SPRING STBuilding
Jul 29, 2026WEBB STBuilding
Jul 29, 2026MASSACHUSETTS AVEBuilding
Jul 29, 2026EFFIE PLBuilding
Jul 28, 2026DANE RDPlumbing
Jul 28, 2026REED STBuilding
Jul 28, 2026WACHUSETT DRBuilding
Jul 28, 2026WACHUSETT DRBuilding
Jul 27, 2026MIDDLE STBuilding
Jul 27, 2026MASSACHUSETTS AVEBuilding
Jul 27, 2026PIPER RDBuilding
Jul 27, 2026FARMCREST AVEBuilding
Jul 24, 2026KENDALL RDBuilding
Jul 24, 2026COMPTON CIRBuilding
Jul 24, 2026LAUREL STBuilding
Jul 24, 2026REED STBuilding
Jul 24, 2026REED STBuilding
Jul 24, 2026REED STBuilding
Jul 24, 2026REED STBuilding
Jul 24, 2026WARD STBuilding
Jul 24, 2026WARD STPlumbing
Jul 24, 2026CLIFFE AVEBuilding
Jul 24, 2026GOFFE RDBuilding
Jul 23, 2026DEPOT SQBuilding
Jul 23, 2026GROVE STBuilding
Jul 23, 2026KENDALL RDBuilding
Jul 23, 2026EAST STBuilding
Jul 22, 2026MARRETT RDBuilding
Jul 22, 2026CAROL LNBuilding
Jul 22, 2026HANCOCK AVEBuilding
Jul 22, 2026CEDAR STBuilding
Jul 21, 2026FAIRLAWN LNBuilding
Jul 21, 2026WOODCLIFFE RDBuilding
Jul 21, 2026CONSTITUTION RDBuilding
Jul 21, 2026DOUGLAS RDBuilding
Jul 21, 2026MASSACHUSETTS AVEBuilding
Jul 21, 2026BLODGETT RDBuilding

Get quotes from local contractors for a project in Lexington.

Permits by type in Lexington

Monthly archive

Before you plan work in Lexington

Lexington's Building Office, at 1625 Massachusetts Avenue, enforces the state building, electrical, plumbing, gas and mechanical codes, the town's zoning bylaws and the Architectural Access Board regulations; issues permits; inspects construction sites; carries out the periodic safety inspections of multi-family dwellings, restaurants, schools, religious institutions, museums and other places of assembly; and levies fines or prosecutes when needed to get compliance. All permits are accepted through the town's OpenGov/ViewPoint Cloud system, and building inspections are requested on a dedicated line, with a separate number for mechanical and sheet metal inspections; the inspectors keep office hours by appointment. Lexington has been accepted into the Municipal Fossil Fuel Free Building Demonstration Program, which lets the town prohibit fossil fuels in new construction and major renovations, and the office links the opt-in specialized stretch energy code and the tenth-edition energy code checklists. It publishes the residential certificate of occupancy requirements, a commercial CO application, gross floor area calculation forms for new homes and additions, a height calculation form and average natural grade worksheet, the residential plot plan requirements, the groundwater bylaw and its review standards, the fence and retaining wall regulations and a temporary tent guide, and posts its building permit activity. The office is open Monday, Wednesday and Thursday 8:30 to 4:30, Tuesday 8:30 to 7 and Friday 8:30 to 1. Jim Kelly is the Building Commissioner, Bruce Dempsey the Assistant Building Commissioner, David Anderson the Building Inspector, James Kennedy the Plumbing and Gas Inspector, Alix Berube the Electrical Inspector and Patrick Ryan the Mechanical Inspector.

Sources: Town of Lexington — Building Office.

Towns near Lexington

Frequently asked questions

Do I need a permit to replace my furnace, boiler or AC in Lexington?

Yes. A gas furnace, boiler or water heater is gas-fitting work, and Massachusetts issues gas permits only to a licensed plumber or gas fitter. Central AC and heat pumps need an electrical permit pulled by a licensed electrician, and Lexington may require a mechanical permit for the equipment. The licensed contractor pulls these permits.

Read the full Massachusetts guide
Do I need a permit to install a heat pump or mini split in Massachusetts?

Yes. The state's guidance is that a ductless mini split is regulated equipment and needs a building permit, and the wiring needs an electrical permit from a licensed electrician. A ducted system adds a sheet metal permit for the ductwork. If you want the Mass Save rebate, the system must also be installed by a contractor in the Mass Save Heat Pump Installer Network.

Read the full Massachusetts guide
Do I need a permit to replace windows in Massachusetts?

Plan on it. Window and door replacement is not on the building code's list of permit-exempt work, and anything that changes a bedroom egress window or the size of an opening is never exempt. Whether a same-size swap counts as an ordinary repair is the local building department's call. On an owner-occupied one- to four-family home the contractor must be a registered Home Improvement Contractor and should pull the permit.

Read the full Massachusetts guide
Do I need a permit to replace siding in Massachusetts?

Plan on it. Residing a house is not among the projects the Massachusetts building code exempts from a permit, and the "ordinary repairs" exemption covers patching, not recladding. On an owner-occupied one- to four-family home the contractor must be a registered Home Improvement Contractor and should pull the permit; the local building department settles borderline cases.

Read the full Massachusetts guide
Do I need a permit to replace my roof in Lexington?

Yes. Re-roofing is not exempt under the Massachusetts building code, so Lexington will expect a building permit, pulled by a licensed construction supervisor. On an owner-occupied one- to four-family home the roofer must also hold Home Improvement Contractor registration.

Read the full Massachusetts guide
How long is a building permit good for in Massachusetts?

Under 780 CMR 105.5, a permit becomes invalid if the work has not started within 180 days of issue, or if the work is suspended or abandoned for 180 days once begun; the building official can extend it in writing for up to 180 days at a time on a written request made before it expires. An application that is filed but not pursued is treated as abandoned after 180 days, with extensions of up to 90 days at a time.

Read the full Massachusetts guide
Are building permits public record, and how do I look one up for an address in Lexington?

Yes, permits are public records. Lexington uses OpenGov, linked at the top of this page, where you can search by address. The recent filings table on this page shows the same public data with the street, date and permit type.

Read the full Massachusetts guide
Can a homeowner pull their own permit?

Sometimes, and it is usually a mistake. The state building code lets the owner-occupant of a one- or two-family home apply for a building permit for their own home, but never for electrical, plumbing or gas work, which only the licensee may do under their own permit. Mass.gov also warns that a homeowner who pulls the building permit may lose eligibility for the Guaranty Fund if a registered contractor's work goes wrong. Let the contractor pull it.

Read the full Massachusetts guide
What happens if work is done without a permit?

The town can order the work stopped, opened up for inspection, corrected, or removed, and unpermitted work surfaces at sale when a buyer's attorney searches the permit history. For electrical work the state's own advice is to hire a licensed electrician to review it, pull a permit for it, and bring it up to code. It is far cheaper to permit it the first time.

Explore Massachusetts

Are you a contractor?

Homeowners in Lexington ask this page for licensed heating, window, roofing and siding contractors. Get listed on masshomecomfort.com and receive those requests.

Get listed on masshomecomfort.com

Permit data for your business

Every Lexington permit above, with the contractor name, valuation, house number and work description, delivered daily by permit type and niche.

See permit alert plans