Are triple-pane windows worth it in Maine?

They lower the U-factor and keep the inner glass warmer, which cuts condensation, but they cost more and weigh more. On the windward or north side of an exposed house the case is strongest; ask for both prices.

My new windows sweat every morning. Are they defective?

Probably not. Water on the room side of the glass means the indoor humidity is high for the outdoor temperature. Water between the panes means a failed seal, which is a defect.

Do I need tempered glass in my bathroom window?

If the bottom of the glass is less than 60 inches above the tub or shower floor and within reach of the water, yes. We check every location the code names before the order goes in.

Buying replacement windows in southern Maine

Three things decide whether a replacement window order goes right: what the label says, whether the opening needs safety glass, and whether a bedroom window still works as an escape opening. In Maine a fourth comes up every January: condensation.

The label

Every rated window carries an NFRC label. Maine's code asks for a U-factor of 0.30 or lower; ENERGY STAR's Northern zone asks for U-0.22 or lower with an SHGC of at least 0.17. How the code reaches a replacement window.

Water on the glass in winter

Condensation forms when warm, humid indoor air meets a surface below its dew point, and in a cold snap the coldest surface in the room is the glass and the frame edge. Single glazing and aluminum frames run wet first; a low-e, gas-filled unit with a warm-edge spacer stays warmer and wets later. If new windows still fog on the inside, the house usually has more humidity than it can handle: check the bath and kitchen fans, and the humidistat if there is one. Condensation between the panes is different: that is a failed seal, and the sealed unit needs replacing.

Safety glazing

Where	The rule
Doors	Glass in any swinging, sliding or bifold door panel.
Next to a door	Within 24 inches of the closed door's edge with the bottom of the glass under 60 inches.
Big, low panes	Over 9 square feet, bottom under 18 inches, top over 36 inches, with a walking surface within 36 inches.
Tubs and showers	Bottom of the glass under 60 inches above the standing surface, unless 60 inches or more away from the water.
Stairs and landings	Bottom of the glass under 36 inches above the walking surface beside stairs or ramps, and near the bottom tread.

Egress

Every sleeping room, and every basement with habitable space, needs at least one emergency escape and rescue opening. Westbrook's and Gorham's code offices print the same figures the code uses:

Requirement	Figure
Net clear opening area	5.7 square feet (5 square feet at grade)
Minimum net clear height	24 inches
Minimum net clear width	20 inches
Sill height above the floor	No more than 44 inches above the floor

An insert double-hung that fits the old frame loses opening size on all four sides, and on the narrow upper-floor windows of an old cape that is often enough to fail the rule. Measure before ordering.

Insert or full-frame

An insert goes inside the existing frame and leaves the interior trim and the exterior casing alone: faster, cheaper, and right when the old frame is sound and square. Full-frame replacement takes the window out to the rough opening, so the sill and the flashing can be rebuilt: the better choice when the sill is soft, the frame is out of square, or the siding is coming off anyway.

Where this comes into the work

Sources: energystar.gov · codes.iccsafe.org · westbrookmaine.gov · gorhammaine.gov · standishme.gov · codes.iccsafe.org · energystar.gov · energystar.gov · energystar.gov · energystar.gov · nfrc.org

Buying replacement windows for a Maine house