Understanding Insulation and R-Value | Ask This Old House
This Old House has been on American television since 1979. It’s not an understatement to say the show is an institution. Homeowners in All Four Seasons Inc. and around the country have been tuning in for decades to see and learn best practices for taking care of their homes.
In this video, the team at This Old House teaches about R-Value and its importance in insulating our homes and keeping them energy efficient.
Video Transcript:
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Tommy, when you say we’re gonna use a dollhouse to talk about insulation, you didn’t tell me at an infrared camera. This is really cool. What do you look at? Well, actually, what I’ve done in a dollhouse is I’ve insulated half of the dogs, okay, and I put some heat lamps inside, right, so by looking through the infrared camera, you can really see the heat loss and where it is. So on this heat is represented by the sort of orangey colors and cooler temperatures represented by the blue, right, so the real bright colors, you can see, the windows have a tremendous amount of heat loss. Yeah, on the left side, you can see the wall and the roof is really bright. So there’s heat loss on that side. And so over here on this side, the roof is kind of blue. And so that’s telling us, the heat is not escaping from the right, and it’s really escaping from the left. Exactly.
Okay. So when you guys talk about insulation, you throw around this term, our value, yes. Well, our value is actually the resistance of heat transfer through the insulation. Okay. And so when I’m thinking about how much insulation I need, what do I think about when you think about two things? Where do you want to put the insulation? And what region do you live in? And when you say, Where are you talking about where throughout the house? Well, whether or not you’re thinking about a wall or a roof, okay, okay, now the biggest heat loss is through the roof, right, so you can always add insulation in your attic, but it’s hard to do it into the wall. So maybe I’m not adding as much to the walls as I am up to the roof. Right. And in terms of where I live region, Alright, so let’s say if you live in the warmer climate, the southern part, the R value that’s required for the roof is our 30.
The middle of the country are 38 and the cold region up near Canada are 49. Okay, so I want to add it to the attic and I live up in a cold region. So I’m definitely going to go up to my attic and add some insulation. How do I know what I have up there? How are you going to measure it so if you climb up into your attic and you may have a roof truss, you may have joist system like this, and you may have insulation lying in between the joists like that. All you need to do is take a tape measure and measure down the side of the insulation. So you touch the top of the plaster jaw, a ball wallboard and you measure the height of the insulation.
This case we have three and a half, right? Alright, three and a half times 3.5 per inch is an R 13. So the R value of this data fiberglass is 3.5 per inch. Exactly. So I want to get to the region that I live in by adding insulation. That’s awesome. Alright, so now I know how much I’ve got. I can think about how much more to add. And most importantly, I can find out that you actually do have a heart. See I do I have a big heart
