How to Use Trees to Save Energy
LESLIE: Well, green home improvement projects that save money and make your home more comfortable are among the most popular improvements to make these days. But there’s one kind of energy-efficient home improvement that is green in more ways than one.
TOM: That’s right. Planting trees of the right size and shape, in the right places, can deliver energy savings for many, many years. Here to help us plan that project is Roger Cook, the lawn-and-garden expert for TV’s This Old House and a guy who’s planted a lot of trees in his career, huh?
ROGER: Yeah. And Tom, it’s pretty exciting to know that the Department of Energy has done studies that show you can save up to 25 percent by strategically planting trees.
TOM: That’s amazing. I mean I don’t think that people realize how successful this can be as a way to save energy. We think about insulating and caulking and things like that but just getting these trees right makes a whole lot of sense.
So, what are the considerations that you have to ask yourself, to help yourself start saving some energy?
ROGER: Well, before, if you even think of trees, if you’re building a new house, consider how you’re going to space the house. You want the living areas with the kitchen to get sunlight all day long so they take in that radiant heat.
TOM: OK. So the orientation of the building is the critical first step, if you have that opportunity. But what if you don’t?
ROGER: Well, then you start thinking about heating and cooling.
Now, if you want to cool the house in the summer, you’re going to plant some deciduous trees on that corner of the house, usually the south or east side of the house. And that’ll block the rays of the sun from hitting the roof and the window.
LESLIE: And a deciduous tree is like an evergreen, sort of dense? Describe that a little bit more.
ROGER: Deciduous trees are the ones that drop their leaves, because that’s going to be great for you. The rest of the season, during the fall and winter, the radiant heat, the sun’s light will be able to get through the tree and heat your house when you need it.
LESLIE: Mm-hmm. OK.
ROGER: On the north side of the house, we would plant an evergreen tree or a row of evergreen trees. And you see these in farms all the time, especially in the Midwest. That’s to protect …
LESLIE: Oh, like a wind block, almost.
ROGER: Exactly. To protect those cold, winter winds from coming in and buffeting the house, no matter …
TOM: Those farmers are pretty smart, huh?
ROGER: Yeah, they’re a lot smarter than we give them credit for. They’ve been doing it a long time, too.
ROGER: You think about those cold, winter winds coming in and hitting your house. No matter how tight we seal it, there’s always cracks and that’s going to blow that cold air into the house.
TOM: Now, Roger, what if we’re in a neighborhood where we just can’t bring in a whole bunch of brand new trees? Can we get some minor benefit by only shading parts of the house?
ROGER: You can. If you have air-conditioner units and you can shade those, they will operate more efficiently. Two ways to shade them. Sometimes we’ll put up a solid fence, which will protect them, or even a row of shrubs to keep the sun from beating on them when they’re operating.
LESLIE: Makes it a lot more attractive, as well. You’re not looking at that condensing unit.
Now, Roger, we get a fair number of calls for folks asking for help when trees get actually too close to the house and impact walkways or foundations. How far should we keep the trees away to get the benefit of that strategic shade but not actually be too close?
ROGER: I would say a minimum is 20 to 25 feet from the house.
TOM: Got it.
ROGER: That gives room for the tree to grow but also for the house to breathe.
TOM: Great advice. Roger Cook from TV’s This Old House, thanks so much for stopping by The Money Pit.
ROGER: Thank you. I had a great time.
TOM: And to see a great video on how to plant trees and save energy, you can visit ThisOldHouse.com.
LESLIE: And you can watch Roger 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 and Ask This Old House are brought to you by The Home Depot. The Home Depot, more saving, more doing.