Attic Insulation Efficiency
LESLIE: Now it’s time to talk to Debbie in Texas about heating and cooling. What can we do for you?DEBBIE: Hi. I built my home seven years ago and I had the insulation blown in the attic and then I put rolled insulation in the walls; the interior walls.TOM: OK.DEBBIE: But the insulation in the attic has packed down a lot and I see that my heating and air conditioning bills are going up.TOM: (overlapping voices) OK. OK.DEBBIE: I’ve heard a lot about radiant barrier. Is that something I should do or could do now that it’s already got that blown insulation in or should I just add more insulation?TOM: Both are good strategies. The radiant barrier does a good job of trying to keep the heat out of the attic to begin with in the summertime; it’s not going to do as much for you in the wintertime. But what you might want to think about doing is adding another layer of insulation on top of what you have. How many inches do you think you have there right now, Debbie?DEBBIE: My guess would be probably eight.TOM: Yeah, that’s not nearly enough. I would add probably at least another 10 or 12 inches. I would use unfaced, fiberglass batt insulation laid perpendicular to the ceiling joists.DEBBIE: Oh, so just lay the rolls instead of having more blown in?TOM: That’s right. You can lay it right on top.LESLIE: (overlapping voices) Mm-hmm, on top.DEBBIE: Oh, OK.TOM: Yeah. This way, you’re going to …DEBBIE: Now, I have those canister lights in the ceiling. Is that going to cause a problem or (inaudible at 0:28:19.8).TOM: Well, they’re already – the canister lights, are they already – is the insulation covering them?DEBBIE: Yes.LESLIE: The blown-in?TOM: OK, it depends on what type of lights. We would hope that the insulation contractor originally checked but if the canister lights, the high hat lights, are rated IC – which simply stands for insulation contact …LESLIE: Then you’re OK.TOM: But if they’re not, then you cannot cover them and you have to go around them.LESLIE: Is there a place on the ceiling can itself where you can read that?TOM: Yes. It should be stamped right on the device itself and if it’s rated …LESLIE: On the interior side. So if you’re looking at it from the room …TOM: Well, it depends on the manufacturer. But usually where you put the bulb in, near the socket, there’s usually some labeling across that so that you can always see it. But it has to be rated for insulation contact; otherwise, you simply want to just go around it.DEBBIE: OK.TOM: Alright?DEBBIE: Alright. Well, thank you. Thank you for taking my call.TOM: Well, you’re very welcome and good luck and we hope we get those heating and cooling bills down.