Lexington, Massachusetts Building Permit Guide

In Lexington, the Building Office of the Land Use, Housing and Development Department, at the Town Office Building on Massachusetts Avenue, issues building permits together with the electrical, plumbing, gas and mechanical permits, and takes every application through the OpenGov / ViewPoint Cloud portal. New buildings must meet the Specialized energy code, in force since January 1, 2024, and the town’s fossil fuel bylaw.

What requires a building permit in Lexington?

The Building Office applies the State Building Code’s rule that construction, alteration, repair, demolition and changes of use need a permit, and it also enforces the electrical, plumbing, gas and mechanical codes and the town’s zoning bylaw. Its own handouts show where Lexington draws lines that matter to homeowners.

A fence that needs no permit still has to follow the zoning rules: posts and holes on your own land, retaining walls set back from the lot line at least as far as they are tall, and stacked fences and walls treated as one if they are closer together than the taller one is high, with the combined height capped at 6 feet. The town’s fence sheet says the boundary must be identified from a stamped, certified plot plan by a Massachusetts licensed land surveyor, and on a corner lot the fence will usually have to come down in height and back from the corner to keep sight lines clear.

What Lexington decides and what the state holds

780 CMR, the State Building Code (10th edition), is written by the Board of Building Regulations and Standards, and Lexington’s rough-inspection checklist cites its residential chapter (Chapter 51, based on the 2021 International Residential Code). The town cannot change it. Lexington’s own rules come from Town Meeting: the zoning bylaw (Chapter 135, the source of the gross floor area and height rules behind the Building Office’s GFA and height forms), the wetland protection bylaw, the demolition delay, the Historic Districts created by special act in 1956 and the Neighborhood Conservation Districts.

On energy, Town Meeting adopted the Municipal Opt-in Specialized Energy Code in March 2023 as Chapter 115 of the bylaws, replacing the Stretch code it had adopted in 2010, effective January 1, 2024. The town was then accepted into the state’s Fossil Fuel Free Building Demonstration Program, and its Regulation of Fossil Fuel Infrastructure bylaw (Chapter 106) took effect on January 1, 2025: no building permit is issued for new buildings and major renovations that install new on-site fossil fuel infrastructure, with exemptions for research laboratories, hospitals and medical offices regulated by the Department of Public Health, clean biomass heating, repairs to unsafe piping, and, for applications filed before January 1, 2027, multifamily buildings over 12,000 square feet that use gas only for water heating.

Lexington building department: who handles permitting

The Building Office, led by Building Commissioner Jim Kelly, issues permits, inspects construction, runs periodic safety inspections of multi-family buildings, restaurants, schools, places of worship, museums and other places of assembly, and levies fines or prosecutes to get code compliance. Its inspectors cover building, plumbing and gas, electrical and mechanical work, and they meet the public by appointment.

The town has warned that fraudulent emails impersonating Town staff have been sent to applicants with cases before the Planning Board, the Historic Districts Commission and Conservation.

Lexington permit types

Every permit, including Historic Districts Commission applications, is started in the OpenGov portal after creating an account. The Building Office publishes the forms that go with a house job: gross floor area calculations (one for new homes, one for additions), a height calculation form, an average natural grade worksheet, residential plot plan requirements and the groundwater bylaw.

Residential permits

A Lexington house permit is built around the plot plan. It must carry the stamp of a licensed land surveyor and show the zoning district, flood zone, easements, every overhang, deck, step and window well with setbacks measured to the furthest point, finished floor and ridge elevations, the spot grades used for average natural grade, generators and transformers, drainage with invert elevations, the driveway and all walls and fences. Because the town joined the state demonstration program, section 115-3B of the bylaws takes the Specialized code’s zero energy and mixed-fuel pathways off the table for new construction and bars new combustion equipment in major renovations, so a new Lexington house is designed all-electric unless an exemption applies. A homeowner may hold the permit for their own one- or two-family home under the state code’s homeowner rule; contractors supervise under a Construction Supervisor License and, on existing owner-occupied homes of one to four units, register as Home Improvement Contractors.

Building or remodeling a home here? Alliance handles residential permit expediting, so the crew isn't waiting on the counter.

Commercial permits

Commercial projects file a separate Commercial CO Application at the end of the job. Under the Specialized code a new multifamily building over 12,000 square feet must meet Passive House standards, and the same demonstration-program limits on the zero energy and mixed-fuel pathways apply to commercial new construction. Owners of parcels with buildings of 25,000 square feet or more also report energy use to the town each year by May 15 under the building energy use bylaw (Chapter 20).

For tenant improvements and new commercial builds, Alliance handles commercial permit applications through issuance. More on this: commercial building permits explained.

What comes before the building permit

• Zoning. The Zoning Division reviews gross floor area, height and setbacks; relief goes to the Zoning Board of Appeals and site plans to the Planning Board.
• Conservation Commission. The wetland bylaw reaches 100 feet from banks, wetlands, ponds, vernal pool habitat and land subject to flooding, or 100 feet from the 100-year storm elevation if that is farther. A hearing is held within 30 days of the filing.
• Historic Districts Commission. Construction, demolition, exterior changes, color changes and signs inside the Historic Districts need its approval. It meets on the first Thursday of the month, the deadline is the meeting a month earlier, and there is no application fee.
• Neighborhood Conservation Districts. Each has its own commission and review.
• Historical Commission. Demolition of a significant building outside the districts triggers the demolition delay.
• DPW, Water and Sewer, Tree Warden. Their sign-offs are collected before a certificate of occupancy, along with Engineering’s.

For the demolition delay, a building is significant if it is on the National Register, in the Historical Commission’s Cultural Resources Inventory, or voted significant by the Commission. After a hearing advertised 14 days ahead, a preferably-preserved building can be held for up to 21 months, cut to 12 months where the lot has approval for multifamily or inclusionary housing.

Lexington permit costs and fees

Lexington’s fee rules come from the Board of Selectmen’s Building Permits and Fees policy, approved July 30, 2012. The per-$1,000 rate itself is not printed on the Building Office’s web pages or in the town code, so ask the Building Office (781-698-4530) for the current rate before budgeting.

Other boards charge their own fees: the Conservation Commission sets wetland filing fees by its own schedule and can require the applicant to pay for outside consultants, while Historic Districts Commission applications are free. Wetland legal notices are published at the applicant’s expense.

Trade permits and who may pull them

• Electrical: filed in OpenGov by a Massachusetts-licensed electrician and inspected by the town’s electrical inspector (781-698-4512).
• Plumbing and gas: licensed plumbers and gas fitters file with the plumbing and gas inspector (781-698-4513); under the fossil fuel bylaw, new gas piping is barred in new buildings and major renovations unless an exemption applies, though repairs to unsafe piping are allowed.
• Mechanical and sheet metal: a separate permit and inspection line (781-730-8485).
• Fire Department: its rough inspection, where applicable, must be approved before the building inspector’s rough.

Each trade’s rough sign-off has to be on the permit card before the building rough inspection is booked.

How to apply for a Lexington building permit

Review, corrections and what causes delay

The building official must issue or refuse a permit in writing within 30 days of the application under 780 CMR 105.3.1. Lexington files tend to slow at the boards rather than the counter: the Historic Districts Commission meets once a month with a deadline a month earlier, wetland hearings must be advertised, and a plot plan without the elevations and grade points needed for the height calculation will be sent back.

Inspections in Lexington

Building inspections are booked by phone at 781-698-4510 and can usually be done the next business day; the contact form is not for inspection requests. Before the rough building inspection, the town’s checklist expects the trade and Fire Department roughs to be signed off, the architect’s or engineer’s inspection report and any civil engineer’s infiltration report to be in, the orange permit card posted with sign-offs, the approved plans on site, and the certified as-built plot plan and basement, first-floor and ridge elevations approved. The under-slab inspection (vapor barrier, radon system vented through the roof) comes before the concrete floor is poured. At the rough, finished grade must sit at least 8 inches below the siding and slope away from the house at least half an inch per foot for the first 10 feet, and the house must be weather-tight, with roof, flashing and weather barrier complete.

For a certificate of occupancy on a single-family house, the town asks for the permit card with all sign-offs, sign-offs from Water, Water and Sewer, the Tree Warden, Engineering and, where applicable, Planning and Conservation, a certified as-built plot plan (driveway at least 5 feet from side and rear lines, slope no more than 12%, and a statement that the house is outside the 2025 FEMA flood plain), the engineer’s infiltration affidavit, a framing letter, the final HERS rating and as-built floor area and height forms. Failing to call the final inspection within 10 working days of finishing costs $50.

Massachusetts building code

Lexington enforces the 10th edition of 780 CMR with the Specialized Energy Code. FEMA’s Community Status Book lists the Town of Lexington (community 250198) as participating in the National Flood Insurance Program, with flood maps current from July 8, 2025.

Massachusetts has one State Building Code, 780 CMR, for every city and town; towns cannot rewrite it, though many opt into a stricter energy code. The trades run under their own state codes. Massachusetts rules

Lexington permit search and official resources

Lexington’s OpenGov portal has a public records search for permits and applications, and public records requests are filed in the same portal.

• Lexington Building Office
• Lexington OpenGov permit portal
• OpenGov public records search
• Specialized Code in Lexington
• Chapter 115, Specialized Energy Code bylaw
• Chapter 106, Regulation of Fossil Fuel Infrastructure
• Select Board policy: building permits and fees (2012)
• Residential plot plan requirements
• Fence and retaining wall regulations
• Rough building inspection checklist
• Residential certificate of occupancy requirements
• Chapter 19, demolition of significant buildings
• Chapter 130, Wetland Protection bylaw
• Historic Districts Commission

Lexington building permit FAQs

Can I install a gas furnace in a new Lexington house?

Generally no. Since January 1, 2025 the fossil fuel bylaw bars on-site fossil fuel piping in new buildings and major renovations, apart from listed exemptions such as labs, hospitals and medical offices.

Which energy code applies in Lexington?

The Municipal Opt-in Specialized Energy Code, adopted by Town Meeting in March 2023 and in effect since January 1, 2024.

Do I need a permit for a fence in Lexington?

Not for a fence under 6 feet on your land. Over 6 feet needs a building permit, over 7 feet a special permit, and front-line fences are limited to 4 feet.

How fast can I get an inspection?

Call 781-698-4510; building inspections can be scheduled for the following business day.

What does starting work without a permit cost?

Triple the scheduled permit fee under the Select Board’s fee policy.

How long can Lexington delay a demolition?

Up to 21 months for a preferably-preserved significant building, or 12 months on a lot approved for multifamily or inclusionary housing.

Can I look up past permits online?

Yes, through the public records search in Lexington’s OpenGov portal; older records can be requested there too.

Simplify Lexington permitting with Alliance Permitting

Alliance Permitting is a permit documentation and submission company in Massachusetts. We prepare your paperwork, file it correctly and coordinate with the permitting authority through issuance. We are not a contractor and we do not perform licensed plan review or inspections; that work stays with your licensed team and the jurisdiction.

This guide is provided by Alliance Permitting for general information about Lexington permitting. Requirements, fees, and procedures change; confirm details with the permitting authority before relying on them.