LESLIE: Talking home building with Peter in New Jersey on WABC. What can we do for you?
PETER: Thomas Edison built a number of cement homes; totally out of cement. They’re still standing.
PETER: I was thinking of building maybe a cement dome home and I was wondering are there certain cements that are less toxic and also does cement have any disadvantages over a wooden house. For instance, does it have more moisture or have negative environmental like effects upon (inaudible)?
TOM: Well, a concrete home is a very earth-friendly home. You mentioned a dome house. One thing to keep in mind is that if you build something that has a very unusual design like that, it may not have the same return on investment as one that’s more traditional.
If you want to build a concrete home, clearly the best way to do that is with something called insulated concrete forms – ICF homes. Insulated concrete forms are basically forms that look like large foam blocks. They kind of look like huge LEGO blocks. And the way you build an ICF house is you stack these blocks up into the shape of the exterior walls on a traditional footing. And then, inside of these blocks these foam blocks are hollow core. And you snap rebar and other types of reinforcing bar inside the blocks and then you pour, from the top down, the entire wall. And as the concrete hardens, the foam blocks stay in place and you end up with a super-insulated wall.
A concrete home that’s built that way needs a third less energy than a traditional home; be it wood or concrete. There’s a terrific website that the Portland Cement Association put together years ago called ConcreteHomes.com that gives you lots of tips on that. But I’ve been a fan of ICF construction for many, many years. And what’s also nice about this block technology is that once you’re done, you don’t have to have a house that looks concrete. You can actually attach wood siding to it if you want to blend in with your neighborhood.
PETER: Well, thank you. And also is there any kind of like more moisture with concrete than a wood house or not really?
TOM: No, not necessarily. The same moisture management principles apply: good grading, good drainage and, you know, proper humidity control inside the house. But it’s got lots of advantages and almost no disadvantages. It’s super-insulated so it requires a smaller furnace, a smaller air conditioning system. It’s also highly storm resistant. And if you build it right, with the exterior walls being the load-bearing structure, you can actually move walls around inside the house as your needs and family changes.
PETER: Thank you very much.
TOM: You’re welcome. Thanks so much for calling us at 888-MONEY-PIT.