"Is your attic well ventilated?" If you've been thinking about replacing your roof or looking into roof repairs, you may be tired of answering this question. After all, attic ventilation can't be that important -- can it? Actually, poor ventilation is quite common, and it can lead to a number of very costly, destructive effects. Here's a look.
If you live somewhere with regular snowfall, then you need to be concerned about ice dams. These are large formations of ice that build up along the edge of your roof. They can slowly work their way under shingles as the water freezes and expands, and before you know it, you're dealing with a leaky roof and rotten wooden underlayment.
Ice dams typically form when an attic is not well ventilated. A lack of ventilation causes warm air to build up in the attic, and the heat eventually starts escaping from the roof itself. This melts the snow at the ridge of the roof, allowing it to trickle down.
More moisture can remain in hot air than in cold air. So, when your attic stays too warm due to a lack of ventilation, the air tends to grow very humid. This problem can be made even worse if your bathroom and kitchen exhaust fans are set up to discharge in the attic! Mold loves moisture, so it does not take long for it to begin growing in a poorly ventilated attic. As fiberglass and cotton insulation are porous, absorbent materials, they're typically the first thing to mold. Since mold can cause breathing difficulties and even nausea, this is not healthy.
Shingles are pretty sturdy, but most do not do well when exposed long-term to excessive heat. When your attic is poorly ventilated, the only way for heat to escape is directly through your shingles. Over time, this puts a lot of wear and tear on them. They might begin peeling in the corners, or granules might start flaking off. Most of the time, shingles come with a warranty, but if the damage is determined to be due to poor roofing ventilation, you may have a hard time getting the company to honor that warranty because most warranties require "correct installation."
If you're noticing any of these signs of poor attic ventilation, talk to a roofing company in your area (like Select Exteriors or a similar location). They can add additional soffit vents or a ridge vent to keep your roof cooler and prevent future damage.