The goal of insulation is to keep your home warm, right? Well, sort of. Attic insulation does keep your home warm in the winter, but in broader terms, it reduces the transfer of heat from your home through the roof. Surely, this keeps your home warmer and your energy bills in check, but it also protects your roof from damage. If your attic is not properly insulated, your shingles may pay the price. Here’s a closer look.
What Happens If Your Attic Is Poorly Insulated?
Hot air rises, so if your attic is not well insulated, then heat from your home is constantly going to seep upward and out through the roofing shingles. Most of the heat will escape from near the peak of the roof, as this is the highest point. Any snow that has accumulated near the peak will melt, and as it trickles down, it will re-freeze along the edge of the roof, forming large sheets of ice known as ice dams.
Ice dams may have a cool name, but they are horrible for your roof. Water expands as it freezes, so if a small portion of this water seeps under the edge of a shingle before it freezes, it then starts prying the shingle off of the roofing surface once it solidifies. Over time, ice dams can lead to extensive leaks and shingle deterioration.
Proper attic insulation prevents ice dam formation. When your attic is well insulated, the air inside the attic stays cool, and so the roof itself stays cool on both its inside and outside. Essentially, your shingles will last longer and you’ll have a lower risk of spring and winter roof leaks if your attic is insulated properly.
How Do You Know If You Have Enough Insulation?
Obviously, if ice dams form on your roof and the air in your attic feels hot in the winter, then your attic is not insulated properly. But you don’t need to wait for winter to judge whether or not you have enough attic insulation.
R-values are used to indicate the ability of a material to block heat transfer. The higher the R-value, the more insulating a material is. In northern climates, attics should be insulated to R-49. This rating is the equivalent of 16-18 inches of fiberglass batt insulation-the most common type. Many poorly insulated older homes only have 4 or 5 inches of insulation. If this is the case, then you need to add more insulation to your attic.
Note that when an attic is properly insulated to R-49 with fiberglass batt insulation, the insulation extends far above the floor joists. If your insulation comes just to the top of the floor joists, which is commonly seen, you need to add more.
What Are Your Best Insulation Options?
Fiberglass batt insulation is very common in the U.S., largely because it is readily available and easy to install. However, it has the downfall of being absorbent. If your roof has any small leaks, the insulation will absorb this moisture and foster a humid environment in your attic. Humidity is not great for your shingles.
Fiberglass insulation serves many homeowners well and is not a terrible choice as long as your roof is in good shape and is free of leaks. However, if you’re looking to make some updates and want to do the very best for your roof and your home, spray foam insulation is often a better option. This dense, water-resistant foam won’t trap moisture if your roof does develop a leak.
Spray foam starts as a liquid and expands into a dense foam as it hits your attic walls. It does need to be applied by a professional, but thanks to its superior insulating ability and resistance to moisture, it can help extend the life of your roof.
If your attic has been poorly insulated for some time-and especially if you’ve seen ice dams on your roofyou may have some shingle damage. Contact Mid-Miami Roofing, Inc to have us come assess the damage and make repairs as needed. Then, improve your insulation so your new shingles don’t suffer the same fate.