Most people do not think twice about their attic, and nowadays most people don’t ever venture up into their attics. If you are like most people then you don’t actually know if your attic insulation is evenly distributed, or if it was actually installed into hard to reach areas. Attic insulation typically lasts around 15-20 years, but loose fill insulation can settle over time and lead to air leaks.
Poor attic insulation (or no attic insulation) is the leading cause of heat and moisture buildup in the attic. This can lead to mold growth and structural deterioration in the attic. In the winter, this can lead to ice dams. An ice dam is a build-up of solid ice that forms along the edges of a roof. This phenomenon got its name because the ice acts as a dam; it prevents water from flowing off of the roof. The presence of gutters usually only furthers an ice damming problem, but they can also form on structures without gutters.
Ice dams form after snow accumulates on the roof after a snowfall. Warm air from inside the home rises, eventually reaching the attic and warming the roof. The warm air causes the snow to melt and run down the roof. When the water reaches the eaves, which do not get warm like the rest of the roof, it refreezes, forming a wall of ice. This ice barrier builds up and forms a dam, which causes melted snow from other parts of the roof to back up behind it. This backed up water can seep through the shingles and cause extensive water damage to the home.
If your attic is not well insulated, then you are losing unnecessary hot air. This leads to increased energy costs in the winter when the hot air seeps out of your attic. In the summer, this can actually have the opposite effect, with hot air leaking into your home, costing more money to cool your home.
Poor attic insulation can lead to multiple problems for your home, roof, and wallet. When your attic is well insulated and sealed up, you will see your energy costs drop, and will lengthen the structural life of your home and roof.