When you think of a roof, you probably think of a structure intended to keep things outside. Indeed, your roof should prevent rain, snow, and chilly air from coming into your home. However, it does also need to be designed to let hot air escape from the attic. Roofs are constructed with vents for this specific purpose. But here's the thing: many roofs are not properly ventilated, either because they were built before builders were so aware of the importance of ventilation, or because someone made a mistake along the way.
How can you tell if your roof is well ventilated?
It's not quite as simple as counting the number of vents or just checking whether vents are present, although that is a good starting point. The number of vents a home needs depends on so many factors, including whether it's one or two stories, what kind of HVAC system it has, and the local climate.
The best way to tell whether your roof is well ventilated is to look for signs that it's not. Here are some of those signs:
You get ice dams in the winter. Assuming you live somewhere that gets snow, keep an eye on the edge of your roof. If there are big sheets of ice up there, that means snow near the peak is melting and trickling down. This happens because a roof is not well ventilated and the heat is instead escaping directly through the shingles.
Your attic is hot and stuffy. If you venture into the attic and it always seems really hot and humid, then it's not well ventilated. You may even feel some of the heat radiating through the ceiling if you place your hand on the ceiling (which is really the attic's floor).
What can you do if your roof is not well ventilated?
Call your local roofing company. They will come take a look and give you their expert opinion, but chances are, if you are experiencing the issues above, they will agree with you that the roof needs more ventilation.
Your roofer will either add more soffit vents, which are the type that are placed under the roof's edge. Alternatively, they might add a ridge vent, which is the type that stretches all along the roof's peak. The best time to add vents is when the roof is already being replaced, but if your lack of ventilation is substantial, your roofer will probably recommend doing this right away.
A lack of ventilation can raise your energy bills and lead to shingle damage, so don't ignore it. Contact a local roofing company for a consultation when you notice a problem.