Roof blistering and hail damage are different in their physical appearance. Blistering, often caused by inadequate ventilation, low-quality material, and improper installation, looks like large, irregular bubbles popping out of your roof. Meanwhile, hail damage is usually circular or oval dents entering your roof and often follows the same path as the hail storm.

In most cases and locations, roofs with a single layer of asphalt roofing shingles won't require roof removal before installing a metal roof. However, underlayment may be necessary on roofs with moderate shingle damage. Heavily damaged roofs or ones with multiple shingle layers will most likely require removal before a metal roof can go on.

Stripping existing shingles and installing a new shingle roof takes a professional one to two days, and sometimes up to three days for larger roofs. Additional safety measures necessary for steep roofs can extend the timeframe even further, as do added measures, like replacing roof decking or reinforcing your roof structure to support heavier materials like slate or clay.

Roofers don’t typically replace vent pipes themselves, but they do handle the flashing and seals around vent pipes when working on a roof. During a roof replacement or repair, roofers inspect the vent pipe flashing for damage, replace deteriorated seals, and ensure the pipe is properly integrated into the roofing system to prevent leaks. If the vent pipe itself is cracked or damaged, a plumber is usually required to replace it, while the roofer ensures the roofing components around the pipe remain watertight.