Technically, yes, an asphalt roof can be replaced in the winter; however, if the replacement is not an immediate need, then waiting until spring or the warmer months is better. Aside from having to work in the cold temperatures, asphalt shingles become less pliable in lower temperatures. Also, the sealant used on the shingles may not activate until the correct temperatures and conditions are reached, which means extra care is required in the installation. Extra care and work need to be implemented in the roof installation during winter, and this can potentially add to the cost of the roof installation, which is also something to consider.