Yes. In the City of Los Angeles, replacing windows needs a building permit even when the new windows are the same size, type and location as the old ones. That kind of like-for-like replacement is an express permit with no plan check, issued online or by appointment at an LADBS permit counter. Changing a window’s size, opening type or location goes through plan check, online through ePlanLA or in person at an LADBS Development Services Center.
Here is how the two routes work, what the replacement windows have to meet, and the extra review that applies in historic districts and near airports.
The two permit routes
| Express e-permit | Plan check | |
|---|---|---|
| Covers | Replacing windows or doors with the same size, opening type and location | Any change in size, opening type or location |
| Plans | None | Two sets of floor plans at 1/4 inch to 1 foot, showing each room’s existing and proposed windows |
| Where | Online, or by appointment at an LADBS permit counter | Online through ePlanLA, or in person at an LADBS Development Services Center |
LADBS also requires structural plans and calculations by a licensed engineer or architect for structures over one story, or where the new window is significantly larger than the existing one. It issues permits to owners as well as contractors. Its express permit list also notes that replacement windows and doors in residential buildings of three stories or less must be dual-glazed and labeled and certified by the National Fenestration Rating Council (NFRC), under California’s energy code.
What replacement windows have to meet
| Requirement | What LADBS lists |
|---|---|
| Energy | Dual glazing, labeled and certified by NFRC |
| Sliding windows | A locking device, plus a device in the upper channel that stops the moving panel from being lifted out when closed or partly open |
| Natural light | Glazing in each habitable room of at least 1/10 of the floor area, and at least 10 square feet |
| Natural ventilation | Openable area of at least 1/20 of the floor area, and at least 5 square feet; at least 1 1/2 square feet in bathrooms |
| Bedroom emergency escape | At least one operable window or exterior door per sleeping room, opening without tools, with a net clear opening of at least 5.7 square feet, at least 24 inches high and 20 inches wide, and a sill no more than 44 inches above the floor |
Older bedroom windows often fall short of those escape dimensions. The 2025 California Residential Code allows for that: a replacement escape window is exempt from the minimum opening size, height and width and the maximum sill height if it is the manufacturer’s largest standard size that fits the existing frame or rough opening, opens the same way or with an equal or larger opening, and is not part of a change of occupancy. It is worth confirming which applies to your windows before ordering.
Homes near the airports
Homes inside a municipal airport noise boundary have to use replacement windows that meet sound standards set by contour. LADBS lists them as follows:
| Noise contour (CNEL) | Openable windows | Fixed windows |
|---|---|---|
| 65 to under 70 dB | Sound Transmission Class (STC) of at least 35 | At least 1/4 inch glass, set in non-hardening glazing material |
| 70 to under 75 dB | STC of at least 40, and air infiltration of no more than 0.5 cubic feet per minute | STC of at least 40, set in non-hardening glazing material |
| 75 dB and over | STC of at least 40 in stucco or masonry walls, or 44 in wood siding or lightweight cladding, with the same air infiltration limit | STC of at least 44, set in non-hardening glazing material |
In the 70 dB and higher contours, LADBS also calls for the joint between the wall opening and the window to be filled with glass fiber insulation and the exterior trim to be continuously caulked.
Historic districts need a separate review
In a Historic Preservation Overlay Zone, Los Angeles City Planning reviews exterior changes, including changes that do not need a building permit at all. Depending on the property and the work, that review is a Certificate of Appropriateness, a Certificate of Compatibility, or a conforming work review. You can check whether a property is in an HPOZ, and how it is designated, on the City’s ZIMAS map.
Outside the City of Los Angeles
Los Angeles County and independent cities such as Pasadena, Burbank and Santa Monica run their own permit processes, so the routes and requirements above apply to addresses inside the City of Los Angeles. For work that is permit-free in the City and the County, see what a homeowner can do without a permit in California.
How we handle it
On a window replacement, we measure, pull the permit, file the energy compliance certificate, coordinate the installation and schedule the inspections. Inside the City, window replacement in Los Angeles covers the LADBS process in more detail, and new openings are covered under window installation.
