Best Roofing Insulation Choices Explored

Often times when a homeowner or property manager is replacing a roof they decide to look into better insulation products.  While there may not be one best roofing insulation choice for all home considering many options is a good idea when you go to replace your roof.  Remember this is probably the easiest time to insulate your attic you will ever have.

Insulating your attic space underneath your roof can greatly extend the life of asphalt shingles as the reduced heat loss puts the shingles through less trauma. However, by far the reason for adding more insulation is to reduce your heating and cooling cost. By stabilizing the temperature in the structure your furnace doesn’t turn on as often. Your air conditioner will even thank you as you reduce the load your putting on it.

The Department of Energy has guidelines for R-Value of insulation to put in your attic although they make no recommendations as to the type of insulation.

R value is simply a measure of a materials resistance to heat passing through it. The higher the better.

roofing r value reccomendations rvalue


Fiberglass Batts 3.1-4.3 Most common insulation found in homes today. This is usually is wall cavities and also seen as the first layer in attics. Simple install stapled or rolls out loose in attc.
Loose Fill Fiberglass 2.5-3.7 Fiberglass that has been cut and formed into loose fill material often sprayed into attic spaces.
Blown Cellulose 3-3.8 Recycled material made predominately from old newspaper. Dry blown – easily acquired at any home store.
R-Board(Hard Boards) 4-8 Rigid panels made from a variety of materials including foam and urethane. Available in varying thicknesses. Either foil backed or not.
Rock Wool 2.5-3.85 Synthetic material sometimes made from left over steel slag or other metal bi products. Hardly used in the last 10 years you will sometimes find this in World War II era structures.
Vacuum Insulated Panels 30-50 You can’t get a better R-Value than these engineered vacuum sealed panels. If you can afford them and don’t mind them loosing some of there insulation value as they lose there seal they are the best.
Icynene 3.6 A expanding spray foam insulation used to insulate between rafters in roofs or side walls. Often used when installing a vent-less roof system.