Know the Thickness of a Cement Driveway
LESLIE: John in Michigan listens to The Money Pit on WKZO and wants to talk about cementing a driveway. What’s going on, John?
JOHN: The driveway is a double-wide driveway and about two (inaudible) long. And it’s gravel. And I wanted to know the thickness of the cement. How thick should the cement be? I’ve got a pickup truck so …
JOHN: … I want to know how much … how thick should the cement be and does it do you any good to buy reinforced fiberglass.
TOM: Great question. You know, the thickness of the cement is not the most important place to start when you’re thinking about putting in a concrete driveway. The most important place to start – and Leslie, I know you’ve been there done that (laughing) – is the prep. Getting that site prepped properly – and by prepped, I mean getting rid of the old stuff, making sure that the base that you’re going to put that cement on is well-tamped so it’s not soft, there’s no rotten material in there.
LESLIE: Well, because if the base isn’t tamped properly and something settles in the wrong way – and settling in any way is wrong when it comes to cement – is that it’ll crack the cement and then you can’t add to that and fix that. So prep is huge.
TOM: As important as the kind of cement and the thickness of cement is that prep. So do the prep very, very carefully.
Now, back to your original question. I do think it’s a good idea to use fiberglass reinforced cement in the driveway. It’s a heck of a lot stronger. If you’re not going to use woven wire mesh, which is like a really extreme way to go but a super-strong way to go, certainly use the fiberglass. And make sure you put it in in sections so that those sections have room to expand and contract. You cannot put a driveway in that is that big without having expansion joints in it.
JOHN: Well, how big should those sections be?
TOM: You said it’s a double-wide driveway?
TOM: So that’s going to be – what? – about, say, 16 … 18 feet wide?
JOHN: I guess about that.
TOM: Yeah. Well, you’re probably going to want to not go more than about 10 to 12 feet without having a joint. So …
JOHN: Okay, well that’s great.
TOM: So you’re going to have several joints going across that driveway as you move up towards the house. Make sure it’s tamped well because if it is tamped, it’s going to not move and you’re going to be happy with that for a long time to come.
JOHN: Can you rent a machine that helps you with that tamping?
TOM: Oh, absolutely. Absolutely. Yeah, a tamping machine is one that can be rented. And it’s definitely worth it with a project of that size. I wouldn’t dream of doing that by myself.
LESLIE: Oh, my god. Could you imagine? That would be the biggest 2×4 …
LESLIE: … ever in life. (laughing)
TOM: Your back would be like falling off. That would be so painful. No, you definitely want to rent a tamping machine for that.
JOHN: Well, what would something like that run? I mean is it a lot of money or …?
TOM: To rent one? I don’t think so. I’m sure it’s going to be less than 100 bucks for the day. But definitely well worth it. Check around with your local rental yard and pick one out.
LESLIE: (overlapping) When you think about the doctor bills for your back.
TOM: (laughing) Yeah, exactly. Less expensive than the hospital visits, that’s for sure, and the chiropractor.
LESLIE: You know it’s like … and it’s hard if you’re tamping it on your own. I’ve done just a patio with like a travertine tile on top of it. And just the patio – say it was 20×10. To do it on your own with a 2×4 with all the layers of sand and however I was doing it, you need a piece that’s going to cover that whole width so you’re making sure that everything is level. It’s a lot of work. And it’s a very strenuous movement. So even on a small space it’s hard work. So with a huge space like that, think about it; it’s worth it.
TOM: You never have too few power tools. Remember that, John. (laughing)
JOHN: Alright. Well, thanks again.
TOM: You’re welcome. Thanks so much for calling us at 888-MONEY-PIT.