Can You Replace a Roof in Winter in New Jersey? What Cold Changes and What Actually Stops the Job

Each shingle maker publishes its own cold-weather instructions, and GAF and Owens Corning both build theirs around 40°F. GAF recommends installing at 40°F (4°C) or above and allows installation below that when the contractor follows its cold-weather precautions. Owens Corning's bulletin TB-10022497-A, printed April 2026, applies when air and surface temperatures are at or below 40°F. Neither names a temperature below which installation is forbidden. Both set a procedure.

CertainTeed's public cold-weather page prints no shingle minimum; it says every product has a minimum installation temperature and to respect it. The instructions for the shingle going on your roof govern, so ask a contractor which maker's cold-weather sheet they will follow, not whether they "do winter work."

Our page on the architectural shingle roof system answers the can-it-be-done question in a paragraph. This post is the detail behind it.

An asphalt shingle carries a factory strip of heat-activated sealant that sun and warmth soften so each course bonds to the one below. Owens Corning says the timing depends on location, roof slope, which way the roof faces the sun and the average daily temperature during and after installation, and that shingles installed in the cold may not seal until warmer temperatures arrive. GAF says unsealed shingles are vulnerable to wind uplift and water getting in.

Until the strip bonds, what holds a shingle down in a gust is its nails and any cement put under it by hand. That is the whole reason for hand-sealing.

GAF's bulletin TAB-R-114 says a shingle that fails to seal for lack of heat is not a manufacturing defect, and its Timberline instructions add that shingles damaged by wind before they seal, or whose sealant gets dirty, may never seal. So a tab that lifts on a January roof is a question of whether the cold-weather procedure was followed.

Once the weather warms and sun reaches the roof, GAF says the shingles finish sealing naturally. The makers describe the hand-sealing a little differently:

The self-adhering membrane at the eaves and valleys is the layer most sensitive to cold, and GAF publishes two numbers that do not quite agree. Its StormGuard installation sheet says to apply it on a dry deck with the air between 45°F and 120°F. Bulletin TAB-R-152 (2021) gives 40°F to 120°F and allows installation below 40°F with precautions. Plan on the stricter number. The precautions:

TAB-R-152 also lists what goes wrong with a membrane laid too cold: an unadhered sheet can move underfoot and cause a fall, unsealed laps let water and dirt in (a dirty lap may never seal), and a too-cold membrane can wrinkle into what GAF calls mole runs that show through the shingles and can open laps to leaks.

If the rest of the deck gets a synthetic underlayment such as GAF's FeltBuster, its sheet (6/19) gives no air-temperature range, but it requires a dry deck, calls the product water resistant and not waterproof, says not to use it as a temporary roof, and notes that its 90-day exposure rating is about UV, not how long it withstands water, snow or wind. Underlayment left bare through a snowstorm is not a roof.

On the shingles, GAF says that below 40°F they lose flexibility and may crack. It advises storing bundles at 70°F for at least 24 hours before installation, carrying up small amounts so they do not cool off, never throwing or dropping them, and flattening stiffened bundles by hand. ARMA adds that cold shingles hold the shape of the stack and must lie flat before nailing, or the nail may break through the surface.

Cold shows up in the tools too. GAF says air compressors struggle to hold pressure, so crews should check it often and keep pneumatic tools stored warm and lubricated; an under-driven nail can puncture the shingle above and an over-driven one can cut the shingle below. GAF also suggests spreading the job over several days and replacing the roof in sections to catch the warmest hours.

The 40°F line triggers a procedure. These conditions should end a work day or push it back:

GAF's case for winter work is short: demand tends to be lower in the cold, so contractors may be more available, and dealing with the roof now avoids the damage that waiting can bring. The cost is the weather-gated schedule above. For a planned roof replacement on a roof that is not leaking, a mild stretch in late fall or waiting for spring are both reasonable.

The forced case starts with stopping the water. After a storm, emergency roof repair covers tarping. If the problem traces to one pipe boot, valley or chimney detail, roof leak repair is usually the honest winter answer, with replacement decided in spring.

Our guide to reading a roofing quote covers the standard lines. GAF states that cool-weather installation does not affect its warranty if all of its application instructions are followed, including cool-weather provisions such as hand-sealing. That is a condition, so a winter quote should say how it will be met:

Permit rules do not change with the season. Whether a roof covering replacement on a detached one- or two-family house needs a permit, and when decking or framing work does, is laid out in our post on the number one cause of roof leaks. If your job needs one, ask who schedules the inspection and what a snow day does to that date. This is general information, not legal advice.

We replace and repair roofs across Bergen, Passaic, Essex and Hudson counties. To have a roof looked at before you decide, call (201) 275-9185. We are registered with the State of New Jersey as a home improvement contractor, HIC reg.# 13VH13970900, and if the honest answer is a repair now and a replacement in April, that is what we will tell you.

Manufacturers revise these sheets, so check the current instructions for your shingle.