How to Give an Old House a Green Makeover
LESLIE: Well, they don’t make them like they used to and that’s a phrase that describes home construction pretty well. In fact, older homes, they were built to last.
TOM: Ah, yes. But older homes were built well before we became so eco-aware. So, what do you do if you want to bring your turn-of-the-century home up to today’s environmental and energy-efficient standards? Kevin O’Connor has got some ideas. He is the host of TV’s This Old House.
KEVIN: Well, hey, it’s good to be here, guys. Thank you for having me.
TOM: And way back when many older homes were built, energy was cheap and we really didn’t seem to care so much about how much was needed to keep comfortable. Any tips on how to take one of those grand, old homes and make it a little more environmentally-friendly and efficient?
KEVIN: Well, you’re right, Tom. We didn’t really care about how energy-efficient they were and I’m not actually sure that there should be any shame on folks who were building them back then. Think about this: in 1950, a barrel of oil cost a little bit under $3 per barrel. Today, it’s hovering around somewhere at $75 a barrel.
TOM: So, Kevin, any tips to start to help get those older homes a little bit more efficient?
KEVIN: Well, I think, generally speaking, older homes are definitely less efficient and it’s mostly because they’re leakier. The air is sort of coming and going in and out of that house. And there are ways that they measure this; they actually talk about air changes. And a typical older home might have the entire air in the house change over four to six times an hour.
So think about that: the air in the house that’s conditioned, either hot or cold, is leaking out of the house and the exterior air is coming into the house. And every time that air changes – every time new air comes into the house – well, what do you have to do? You have to heat it or cool it again and that requires resources and that costs money.
LESLIE: Well and I think it’s important – you know, there’s been so many advances in the technology to figure out exactly where these air leaks are in your home – whether it’s through a blower-door test or that geothermal screening where they’ve got the color differentiations to show you exactly where you’re losing the heated air – that can help you really pinpoint where you should do your best work.
KEVIN: There is an industry out there right now – professionals who are in the business of home energy audits – and they’ll do those blower-door tests that you talk about, Leslie. They’ll come in and they’ll give you exact, scientific measurements about that air movement.
You can actually rent an infrared camera now from some of the home centers. You can go down there and in the course of a weekend, for $75, have that tool in your hand and see where the heat is escaping. That information is powerful for you, as you start to pursue where you’re going to plug these leaks.
TOM: Yeah and that’s really true, because I think we get into analysis paralysis; we don’t know where to put the energy dollars. Do I get windows? Do I get doors? Do I insulate? Do I caulk? Do I weatherstrip? You really can’t know where you’re going to get the best return on investment and skills of the professionals like that do help you really narrow it down and make some really smart decisions.
KEVIN: They’re complicated beasts, our homes. There are sophisticated systems that are inside of them and there’s no shame in relying on a professional to give you some guidance.
You can make some very basic rules, however, or I should say a list, however. And for me, it starts with insulation. You really can’t have too much insulation in a house. And so, if you have an older house, it’s probably underinsulated.
And I would start by adding insulation if you don’t have any or increasing the amount of insulation that you have in your attic. It’s often easy to do and you can sort of do it kind of sloppily, because you’re not trying to put it behind your finished walls. So you can blow in cellulose or lay down fiberglass batts and you’ll get a big bang for your buck on that.
For the basement, I’d move to the …
LESLIE: Well and Kevin, let me just jump in one second. The attic. What’s a good rule of thumb for the amount of insulation you should really have up there?
KEVIN: My rule of thumb is you can’t have too much.
LESLIE: Right. But for somebody who’s not going to fill joist to rafter with insulation, where should you stop?
KEVIN: Fill the joist bays. I mean that is a great place to start. Your joist bays …
TOM: That’s the minimum.
KEVIN: Yeah, that is the minimum.
KEVIN: Fill those joist bays because you’ve got a cavity there; you can get it in. But I would say go over the joist bays, as well, because you’ve got natural seams between the joists and the second that you start to go over the joist bays, you’re not only adding insulation but you’re also cutting down on the number of those seams and cutting down, therefore, on air flow.
TOM: That’s right. And the key there is to go perpendicular on the second layer of insulation and to use unfaced insulation so you don’t trap any moisture inside there.
LESLIE: Now with insulation, I think there’s some confusion. People don’t always know which direction to put that vapor barrier or the facing, too, when they’re installing this insulation.
KEVIN: No, I think you’re dead-on here. There is quite a bit of confusion where you put this vapor retarder. And there, unfortunately, isn’t a single, simple answer. The vapor retarder is trying to prevent condensation from occurring, basically, in the insulation. And it really depends on how you’re heating and cooling your house, how often you’re doing one or the other, what type of insulation you’re working with and where you live. And so you can get lost in that matrix pretty quickly.
But a professional who’s familiar with this can sort it out for you in just a minute, so it’s a good thing to consult with someone who knows what they’re talking about.
TOM: And that’s the place to start. Kevin O’Connor, host of TV’s This Old House, thanks so much for stopping by The Money Pit. Great advice.
And you can get more from the team at This Old House by visiting them online at ThisOldHouse.com.
LESLIE: And you can watch Kevin and the entire This Old House team on This Old House and Ask This Old House, on your local PBS station.
TOM: And This Old House is brought to you by Lumber Liquidators. Lumber Liquidators, hardwood floors for less.