What is the R-value of insulation?
Of course, we all know insulation can keep us cooler and save us money on the a/c bill, but it is something homeowners often neglect because we don’t often look to see what’s going on in our attics. Insulation is critical for slowing down the transfer of heat from your roof through your attic and ceiling and into your home. How much it slows down the transfer of heat is its “R-Value.” R-value measures an insulation’s resistance to heat flow. The R-value depends on the type of material, thickness, and density. The higher the R-value, the better the insulation is at doing its job. The R-Value is measured by inches, so when you’re purchasing insulation, the R-Value should be written on the packaging.
Building codes in Florida recommend ceiling insulation with an R-value of at least 30. The US Department of Energy recommends an R-value of 38 for attics in Florida. Here’s a helpful R-Value chart provided by The Home Depot.
How do you know if it’s working?
I suggest you open the access hatch to your attic and take a look. With a strong flashlight, you should be able to see a good portion of your attic and may not even need to get fully up there. What are you looking for? Insulation tends to compact over time. How deep and dense is your insulation? Are there any thin or bare areas? Also, if you see any shrinkage, tears, holes, discoloration, or pest activity (rats made some pretty impressive tunnels in my insulation), you might consider replacing what you have. I’ve seen many home inspection reports where the insulation in an attic was nearly non-existent.
Who can install insulation?
Insulating can be a DIY project, but I suggest consulting a professional because there are different options, depending on your house. I’m sure you’re all familiar with the pink fiberglass roll-out type, which is the most cost-effective. There’s also blown-in, spray foam, rigid foam board, and radiant heat barriers (my attic is a combo of blown-in and a radiant heat barrier). And new high-efficiency products are being created all the time. You can expect to pay from $1.50 to $2.45 per square foot, depending on what you have installed. You will quickly see the return from your savings on your a/c bills.
