Part one can be found here: https://www.jefftallonenterprises.com/blog/ice-dam-prevention-part-1
One of the most challenging heat sources in an attic can be chimneys. Make sure the flashing around the chimneys is in good shape. If you have a masonry chimney, seal only with a fire stop sealant. DO NOT use spray foam or regular insulation, that’s not safe. If you have a stainless chimney, consider having a box built around it, but you have to be very careful and observe proper clearances to that pipe. This is not a do it yourself project and should only be done by an insured, experienced mechanic.
Check for electrical cables and other things that enter attic from below. Many times, you will see dirty insulation around them. This is caused by leaking air from below. Once again, the best way to seal is a fire stop sealant.
Once you have eliminated heat sources from the attic, consider another layer of insulation. There are several types of insulation as well as ways to install. Even a home built with a blown in 12” or R38 rated insulation can be compromised over many years of settling, moisture saturation or rodent holes. Rolls of insulation can be rolled over it or additional insulation can be blown in. Just make sure it’s even and isn’t touching the roof deck, as mentioned in part one.
Once you have tried all the common ways to eliminate your ice dams and you still have the issue, you need a designed, efficient ice melt system. Why is that? Could be the style of house. Cape Cod style homes, with a “knee wall” upstairs are a very common home style we see with ice dams. Maybe the architect that designed your house didn’t consider potential areas that would lead to damaging ice dams. Regardless of how it got that way, your best way to safely deal with the hazards of ice build-up and their lethal icicles is the installation of a good ice melt system. Taking pictures of the problem areas, especially in the winter, can be a big help. This will help us determine the severity of the problem and what areas need special attention. It’s best to install these systems when it’s safe to climb on the roof, but if it’s fall and you haven’t seen ice for 6 months, a picture is truly worth a thousand words.
Check out some of the products we use here: https://www.jefftallonenterprises.com/ice-dam