More often, roofs are required to do more than just protect us. Residential and commercial roofs are now seen as a significant contributor to a building’s energy usage. Adding a layer of insulation under your roofing materials can go a long way toward reducing heating and cooling costs.
How? Insulated roofing systems can help hold in the heat during the cold winter months and in the summer, they can prevent the baking rays of the sun and the extreme temperatures that build up over a roof from descending through the roof into the building.
There are a number of options to choose from. Some insulated systems are tapered, which means they are designed to increase the slope of a roof in order to drastically reduce or eliminate the amount of standing water on the membrane.
There are many types of insulation, among the most commonly used being polyisocyanurate, polystyrene and perlite, each with its own advantages. Those include:
- Polyisocyanurate: According to the 1999 NRCA Market Survey, polyisocyanurate, also called polyiso, is the most widely used insulation product in the roofing industry. It has the highest R-value – a measure of thermal performance — of any insulation product. It is also lightweight, fire-resistant and compatible with most roofing system applications.
- Polystyrene: Lightweight and 100% recyclable, polystyrene is also inexpensive. Unfortunately, polystyrene is extremely difficult to use with hot asphalt and is attacked by most solvent-based adhesives. Still, one can handle these problems by using an inverted roof system, embedding the polystyrene into lightweight concrete or combining it with a more heat-resistant insulation.
- Perlite: Made from perlite volcanic ore, this board is acceptable for Class I construction, and can be secured to the roof deck mechanically. It is fire resistant, has good moisture resistance, excellent dimensional stability and generally acceptable mechanical stability. While Its R-value is low, it is stable.
The ideal choice? Of course, cost is a factor, as is R-value (the higher the better). But care must be taken to ensure that the insulation is compatible with the roofing membrane.
In business since 1985, ROOFCORP’s has been installing roofs and roofing materials for close to 30 years. Contact us today to hear about the best insulation options for your project.