Installing roofing shingles in cold weather is dangerous.
Going up on your roof in cold weather, especially when there is ice or snow is potentially very dangerous indeed. Any traffic on your roof should be avoided wherever possible because a slippery roof is likely to result in a very serious fall. If you do have to go on the roof to conduct repairs you should always ensure that the roof itself, ladders and any equipment you will be using is dry and safely secured.
You can damage material if installing roofing shingles in cold weather.
Removing ice or snow from the roof can cause serious and irreparable damage to the roof. Scarping away at anything on your roof can easily lead to you removing the protective surface on the shingles, and this surface is the best protection you can get against the elements. It prevents damage to the material itself and ensures that any water will run smoothly off your roof surface without collecting. Removing it means your roof is more prone to leakage. Also, the slightest knock to a freezing cold shingle is likely to break it very easily.
Things to consider when installing roofing shingles in cold weather.
The most important thing to remember in the event that you need to install roofing shingles in cold weather is your personal safety. Traversing a sloping roof in icy conditions is near suicidal and should be avoided at all costs. There is a reason that you can’t get a roofing contractor to come out and fix your roof in these conditions and it isn’t because it’s too cold to work. Snow is no better and even early morning dew can create a very slippery surface that is potentially lethal to anyone trying to walk on the roof. However, if you do need to replace a shingle try to remain on the ladder and be sure to handle the shingles with as much care as possible so that you don’t break them. You will have to manually seal the tabs of the shingles down yourself, because the warmth of the sun normally activates the adhesive strips, but this obviously will not be possible in cold weather.