Window Replacement in Portland and Southern Maine

When replacing beats repairing

Replacement makes sense when the frame or sash is the problem, not just the glass:

• Rot in the sill or the bottom rail of the sash, soft to a screwdriver.
• Aluminum frames that sweat and frost all winter, wetting the sills and drywall returns.
• Sashes that will not stay up, will not lock, or let daylight past the meeting rail.
• A bedroom window too small to serve as an escape opening.
• Early vinyl units with warped frames, where new glass would not fix the air leaks.

When the frame is sound and only the sealed glass has fogged, replacing the glass costs a fraction of a new unit. When the house is old and the sash is original old-growth wood, repair plus a low-e storm can match much of a new window's performance. We will say which one we think you have.

The efficiency figure Maine requires

Maine applies one energy code in every town, the 2021 International Energy Conservation Code, and in this part of the state it puts a ceiling of U-0.30 on a window, with nothing required of its solar heat gain. Under the code's replacement-window provision, a new unit going into an existing opening has to meet that number, whether or not the town inspects. Kennebunk, for one, requires a permit for replacement windows precisely because the energy code applies to them.

Treat the code figure as a floor, not a target; the label on the window you are quoted states its own U-factor. The number worth ordering to is ENERGY STAR's: in the Northern zone, which covers all three counties here, U-0.22 or lower with a solar heat gain of at least 0.17. How the code and ENERGY STAR compare.

Which towns want a permit for windows

Town rules on window swaps split clearly:

Cutting a bigger hole means a new header over it, and the town rules we read all treat that as structural work needing a permit. The permit guide has all 64 towns.

Pocket insert or full tear-out

There are two ways to put a new window in an old opening.

A pocket insert slides into the old frame after the sashes and stops come out. The interior trim and the exterior casing stay. It is quicker and less disruptive, and it suits a frame that is square, dry and solid. The cost is glass area: the new frame sits inside the old one and narrows the opening on every side.

A full-frame replacement takes everything back to the rough opening. That allows a new sill pan, new flashing lapped into the wall's barrier, and insulation in the gap around the unit. It is the right choice when the old sill is soft, when the frame has racked out of square, when a bedroom window needs every inch of opening for egress, and whenever the siding is coming off anyway.

On old Maine houses with wide original casings, a full-frame job can usually keep or rebuild the exterior trim so the house does not lose its look.

Flashing a window into an old Maine wall

Houses built before about 1940 here have board sheathing and no barrier behind the siding, and their windows were trimmed, painted and caulked rather than flashed. A new window set into that wall needs its water management built from scratch:

1. A sill pan or sloped sill flashing that turns up at the back and the ends, so water that gets under the window drains out the front.
2. Flashing tape or membrane at the jambs, lapped over the sill flashing.
3. A head flashing or drip cap over the top, lapped under whatever barrier or siding sits above.
4. Low-expansion foam or backer rod and sealant at the interior, so warm, moist room air does not reach the cold frame and condense there.

Wind-driven rain is the test here. A nor'easter can push water up and sideways at a window for hours, and the flashing order above is what keeps it outside.

Frame materials for this climate

Every common frame material is sold for northern climates. The trade-offs:

• Vinyl: the best value and low upkeep; darker colors and very large units move more with temperature.
• Fiberglass: stiff and stable in large sizes, and it takes paint.
• Wood: the traditional look and the one historic review boards prefer; needs paint on the outside unless clad.
• Clad wood: wood inside, aluminum or vinyl outside; looks right on an old house with less exterior upkeep.

Glass matters as much as the frame. Low-e coatings, argon or krypton fill and a warm-edge spacer set the U-factor, and a triple-pane unit lowers it further and keeps the inner glass warmer in a cold snap. Whether triple pane pays for itself depends on the wall, the exposure and how you heat; we can price both.

Historic districts and old paint

In several towns here the window itself is reviewed. Saco requires a certificate of appropriateness to replace wooden window sash in its districts and asks that historic sash be kept wherever reasonably possible. Biddeford reviews any change in window sash beyond minor repair. Freeport's design review districts let the Town Planner approve same-size windows, provided the old lite pattern is kept with true or simulated divided lites, and Brunswick's board reviews changes to muntin profiles.

On any house built before 1978, replacing a window is always covered by the federal lead-safe rule, however small the job: the firm is EPA-certified, a certified renovator is in charge, the work area is contained and you get EPA's pamphlet first. Town-by-town historic rules and the lead rule have the details.

Savings, price and the contract

New windows make a house more comfortable and quieter, and they do cut heating bills, but slowly. ENERGY STAR's 2023 modeling for its Northern zone puts the saving from a whole-house replacement at about $568 a year over single-pane glass and $282 over older double-pane. Half the homes in the metro heat with oil, by the Census count, so what a saved gallon is worth shifts from winter to winter.

Price depends on the number and size of openings, insert or full-frame, frame material and glass package, and any trim or rot repair found when the old units come out. Maine's Home Construction Contracts Act names window replacements as home construction, so any job over $3,000 is written up and signed before work starts, with the deposit held to a third of the price. A window ordered on a contract signed at your door after an uninvited sales visit cannot be installed until your three-day right to cancel has run out.

Common questions about window replacement in Portland

Where we work

Window replacement across greater Portland and southern Maine: Cumberland, York and Sagadahoc counties, from the islands of Casco Bay to the Sebago Lake towns and the New Hampshire line. Each city has its own page with the permit rule and code edition that apply there: