Summer in the low country can get pretty hot, but the tempurature in a traditional attic on a warm, sunny can get as warm as 140 degrees! That's because there is nothing blocking the radiant heat coming through the roof from entering your attic. And a traditional attic, in spite of what many think, is actually OUTSIDE of the envelope of your home. It exchanges air and humidity with the outside. All those vents and openings are invitations for bugs, birds, bats and critters, too.
With spray foam, the envelope of the house is extended to the roof, not just to the ceiling. The attic becomes part of the inside of your home and the temperature in the attic rarely rises more than 10 to 15 degrees above the tempurature of your home. The underside of your roof is coated with open cell foam and the ridge, gable and soffet vents are closed off. Think of it as adding a dormer with no doors or windows. Open cell foam also absorbs sound, so your attic and home will be much quieter.
Do you have air conditioning equipment in your attic? Compare it to your automobile. Think about how hard your air conditioner has to work when you first get in your car on a hot day. The situation is very similar for your attic based A/C and ductwork. That equipment has to work very hard in the summer and in a traditional attic, it is working in that insane heat. In a sprayfoamed attic, the operating temperature of that equipment drops dramatically, saving energy and money. And often times, there are leaks in the ductwork in attics. In a traditional attic, those leaks adversely affect the cooling of your home. In a sprayfoamed attic, those leaks become useful by helping to control attic temperatures. We often encounter homeowners who have been told that they need to replace the air conditioning ductwork in their attic, often at great expense, because it leaks. Doesn't it make more sense to eliminate the source of heat in your attic so any air leaks you may have work for you?