Roof insulation continues to be a hot topic, especially among homeowners with older houses looking for ways to reduce their energy bills. Although roof insulation standards became part of building codes in the early 1970s, the minimum requirements serve as a starting point and should be increased depending on the style of your home and its location.
The 411 on Roof Insulation Materials
The purpose of roof insulation is to ensure that air is not escaping from your home through the roof. It acts as a secondary barrier to other wall, ceiling, or attic insulation installed in your home.
All insulation for roofs is distinguishable by an R-value. The R-value reflects the insulating capacity, so if you live in a cold climate, you’ll want roof insulation that has a high R-value number. To see what the R-value is for your area, check out this helpful U.S. map from the U.S. Environmental Protection Agency that indicates your recommended levels of insulation.
There are many different kinds of roofing insulation, categorized into two main types: reflective insulation and bulk insulation.
- Reflective insulating material
- Uses a combination of different kinds of insulation, like fiberglass, plus low emittance surfaces like foil, plus trapped air spaces to create highly energy efficient insulation. It’s called reflective because it reflects rather than absorbs heat. So when you’re using your heating system, it reflects the heat inside your house back into it so it doesn’t escape through the roof. And when using your cooling system, it reflects the sun’s heat so it doesn’t overheat the surface of your roof and overwork your air conditioning.
- Bulk insulating material
- Blocks heat flow in or out of the home. It relies on air spaces between fibers, bubbles, or foam of insulating materials to trap heat and prevent it from escaping.
Roof insulating materials also differ by their usage, with some limited to new home builds and others for new and existing roofs. Among the most popular roofing insulation types are fiberglass, cellulose, rigid boards, blankets, wood fibers and foam insulation.
Choosing Your Insulation Type
The Roofing Annex can guide you in choosing the best roof insulation materials based on your budget, the style of your roof, the type of roofing materials used and whether you are building a new home or replacing an existing roof. As roofing specialists, we also take added precautions to ensure the roofing insulation selected for your home design does not cause other problems, such as interior moisture condensation.
If you are unsure about whether your roof is insulated or the type of insulation in use, ask one of our roofing specialists during your next roof inspection (you should have your roof inspected twice a year; we recommend early spring and fall). We’ll let you know the condition of your roofing components and whether they are the most energy efficient as they can be.
Keep in mind that the quality of the roofing insulation you buy will translate into better savings because with better insulation, you are losing less energy and saving more on your utility bills.