Window Replacement in Philadelphia, Pennsylvania

In Philadelphia, a same-size window replacement on a one- or two-family home may need no building permit. The Department of Licenses and Inspections (L&I) says no permit is required for replacing non-fire-resistance-rated windows without structural change on one- and two-family dwellings, with no change in the location, shape or size of the existing openings (L&I EZ Permit Standards, Windows and Doors) ¹. Other replacements may use L&I's EZ permit, which lets an applicant get a permit without submitting plans when the job meets its conditions; changing the location or size of a window, or cutting a new opening, falls outside that route ¹.

Two more city rules shape a window job here. L&I says a business doing construction or repair work needs a Philadelphia contractor license, unless it only works on existing one- or two-family dwellings, in which case it submits as a Home Improvement Contractor after registering with the state (L&I contractor license) ². And on a property listed on the Philadelphia Register of Historic Places, the city says changes, windows included, need Philadelphia Historical Commission approval (Get approval for work to a historic property) ⁵. The statewide registration rules are on the Pennsylvania page.

Do you need a permit to replace windows in Philadelphia?

L&I's EZ Permit Standards for windows and doors (revised June 2026, on the 2021 IECC, IRC and IBC) let an applicant get a permit without submitting plans when the job meets its conditions; any deviation "will result in permit revocation" (EZ Permit Standards) ¹. The main conditions:

• The new window stays in the same location and is the same size as the original opening ¹.
• The opening is at least 30 feet from any interior lot line ¹.
• The EZ route does not apply to buildings with more than 40% vertical fenestration on above-grade walls, to buildings listed as historic by the Historical Commission, to changes in location or size, or to new openings ¹.
• It also excludes openings more than 72 inches above finished grade or the surface below where the lowest part of the clear opening is 24 inches or less above the finished floor ¹.
• Facade alterations in named areas, among them Society Hill Northeast, the Chestnut and Walnut Street area, historic districts and several conservation overlays, must be approved by the Philadelphia City Planning Commission ¹.

The same standard sets construction requirements: openings between the window and its jambs and framing must be sealed, replacement windows may have a U-factor of no more than 0.32, and operable windows located wholly or partly within 6 feet above ground level or an exterior walking surface need a window opening control device ¹. Safety glazing is required in hazardous locations, such as glass in or next to doors and large panes near the floor ¹.

Home Improvement Contractors can apply for permits online through eCLIPSE, L&I's online system, or in person at the Permit and License Center by appointment (PA Home Improvement Contractor permits) ³. L&I's contractor information page tells owners to confirm the contractor has the required permits and has posted them on the property before work begins ⁴. The article on window replacement permits compares Philadelphia's rule with other cities.

Who may do the work

L&I's contractor license page says a business needs a Philadelphia contractor license when its work involves construction, demolition or repair and does not require a specialized company license (such as electrical or plumbing). A business that only works on existing one- or two-family dwellings does not need this license; it must instead submit as a Home Improvement Contractor after registering with the state (L&I contractor license) ². The license page lists requirements including a certificate of insurance, proof that a supervisor completed an approved OSHA 30 safety course within five years of the application, and being current on all city taxes; it says the license must be renewed annually ².

For home improvement work on one- and two-family homes, L&I's Home Improvement Contractor page says only those registered with the Pennsylvania Attorney General can use that service, and they must show proof of registration, the same $500,000 general liability minimum and current city taxes (PA Home Improvement Contractor permits) ³.

The same page also says the Attorney General's registration system is currently down and cannot issue or renew registrations, and it describes interim steps L&I uses until service is restored ³.

To check, L&I's contractor information page points to its online contractor lookup, which it describes as a listing of all contractors with an active Philadelphia license and any licensing violations they have, and to the Attorney General's Home Improvement Contractor Search for state registrations ⁴. Questions to ask an installer:

• Does your business hold a Philadelphia contractor license, or will you submit as a PA Home Improvement Contractor for my one- or two-family home?
• Does the name in the L&I lookup or the Attorney General search match the name on the contract?
• Who will pull the permit, if one is needed, and is its cost in the quote?

The guide on how to choose a window installer covers references and warranties.

Historic properties: Historical Commission review

If a property is on the Philadelphia Register of Historic Places, the Historical Commission's approval is needed to change it, and its review covers the installation, alteration, repair, removal, replacement or covering of windows and storm windows (Get approval for work to a historic property) ⁵. Routine upkeep such as replacing clear window glass is exempt ⁵. Review can be requested electronically through eCLIPSE or in person by appointment; staff often approve applications without referral, and those they cannot approve go to the Architectural Committee, which makes a recommendation at a public meeting, and then to the Commission at its own public meeting ⁵. The page says there is no charge for a project review by the Commission or its staff ⁵.

The Commission's page for property owners adds that if your designated property has non-historic windows, you will not be required to restore them, but you need the Commission's approval if you decide to replace them (Information for property owners) ⁶. Remember too that historic buildings cannot use L&I's EZ permit route ¹. If your home is listed, ask whether the installer has worked through a Historical Commission review before. The article on storm windows covers one alternative to replacement.

Climate and glass for Philadelphia

ENERGY STAR places Philadelphia County in its North-Central zone (ENERGY STAR climate zone finder) ⁸. There, Version 7.0 criteria call for a U-factor of 0.25 or less and a solar heat gain coefficient (SHGC) of 0.40 or less, with an air leakage limit of 0.3 cubic feet per minute per square foot (ENERGY STAR criteria) ⁷. That U-factor is lower than the 0.32 maximum in L&I's EZ standard ¹⁷.

NOAA's 1991-2020 normals for Philadelphia International Airport give a winter (December to February) average of 36.1°F, a summer (June to August) average of 76.4°F and normal snowfall of 23.1 inches a year ⁹. The station logs about 4,510 heating degree days and about 1,360 cooling degree days a year, so a window here works in both seasons ⁹.

U-factor measures how fast heat moves through the whole window; lower insulates better. SHGC is the share of the sun's heat that passes through the glass. The articles on U-factor and low-E glass explain both.

What windows cost in Philadelphia

This article does not quote a Philadelphia price; the survey figure here is national. Fixr reports about $800 per window, typically $450 to $1,200 (updated January 21, 2026) ¹⁰. The window replacement cost guide sets several surveys side by side and explains what moves the price.

Getting quotes

Ask each installer for the same window, glass and installation method in writing, plus the license or registration number. The article on how to compare window quotes gives a line-by-line template. When you are ready, you can compare quotes from window installers.

About these figures

• ¹ Official record: L&I EZ Permit Standards for windows and doors, revised June 2026 (no permit for same-size non-rated replacement on one- and two-family dwellings; 30-foot, 40%, 72-inch and 24-inch conditions; historic exclusion; U-factor 0.32; 6-foot opening control rule), checked October 26, 2026.
• ² Official record: L&I contractor license page (who needs it, the one- and two-family exception, $500,000 general liability per occurrence, supervisor OSHA 30 within five years, annual renewal), checked October 26, 2026.
• ³ Official record: L&I page on submitting permits as a PA Home Improvement Contractor (eCLIPSE or in person, proof of registration, $500,000 general liability, taxes, notice that the state registration system is down), checked October 26, 2026.
• ⁴ Official record: L&I contractor information page (contractor lookup, Attorney General database, permits posted before work), checked October 26, 2026.
• ⁵ Official record: Historical Commission approval page (windows in scope, clear glass replacement exempt, review through eCLIPSE or in person, no charge for review), checked October 26, 2026.
• ⁶ Official record: Historical Commission information for property owners (non-historic windows and replacement approval), checked October 26, 2026.
• ⁷ Official record: ENERGY STAR Version 7.0 window criteria (North-Central U-factor 0.25, SHGC 0.40, air leakage 0.3), checked October 26, 2026.
• ⁸ Official record: ENERGY STAR county climate zone finder (Philadelphia County in North-Central), checked October 26, 2026.
• ⁹ Official record: NOAA NCEI 1991-2020 normals for Philadelphia International Airport (winter 36.1°F, summer 76.4°F, snowfall 23.1 inches, heating degree days 4,510, cooling degree days 1,358), checked October 26, 2026.
• ¹⁰ Reported: Fixr national per-window cost, about $800, typically $450 to $1,200, updated January 21, 2026, checked October 26, 2026.