# Inspired by 'Fumes concrete thread, a concrete question

Discussion in 'The Lounge' started by newyorkin, Feb 6, 2004.

1. ### newyorkin1 ton status

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Inspired by \'Fumes concrete thread, a concrete question

I happen to be in driveway misery right now... Fumes post gave me helpful info on concrete, but to expand on that a little?

I'm going to need enough concrete for a 75'x10' driveway. At 4" thick, the calculator said I need 9.17 cubic yards. At 5", I need 11+ CY.

What thickness should I be thinking about for a driveway of this length?
Also, one guy I talked to asked if I wanted 2000 or 3000 psi. What should I go for? A 6000lb K5 will probably be the most weight this driveway ever sees (1500lbs per wheel, conservatively 4sq inch of wheel on surface = 375psi; is this safe?).

I also want it to slope a little to send water to the road. Anyone have a suggestion for the degree of the slope needed? That'll help me figure how high it needs to be at the end.

Thanks all.

2. ### landsmasher1/2 ton status

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Re: Inspired by \'Fumes concrete thread, a concrete question

Here's the thing with driveways. First you want to use metal wire mesh at 4 to 6 inch squares. At the bottom of the driveway where it meets the road you want it to go to 6" thick. 4 inches thick is fine for the rest. You also want to make sure to put expansion joints in the concrete every 8 feet. As far as slope is concerned, what ever slope works best for your situation is fine as long as there is at least a 1/4 bubble on the level of slope. That is the usuall runoff figure for anything.

For 11+ yards you will want to order 2 - 6 yard trucks. Have one show up about 45 minutes after the other one shows up. A half hour is all you need for the first one if that.

For driveways and slabs, you should really hire a concrete guy. This is not something you want to do yourself. You may find yourself paying \$1 per minute for the drivers hanging around while you try to get your sh!t together. You also need to know how to finish the concrete. That's not to mention the forming. Get some bids and do it right...

3. ### skratch1/2 ton status

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Re: Inspired by \'Fumes concrete thread, a concrete question

The bulk of the driveways that we do is with what is called 6 bag mix. I think that comes out around 3000psi.
That should be fine unless you intend to drive something heavier on it (like a semi or box truck).
Also most of the drives we do seem to be deeper than 4" more like 5" to 6" and a bit thicker at the edges to help prevent cracking.

75 ft is a looooong drive, I'd work it in stages so as not to have problems with the mix setting up to quickly before it gets finished, unless you have quite a few guys working on it.
I don't recall exactly what slope most guys were using on the longer drives, but I think it was something like 2" drop for every 10 feet or something like that. Also you may want the center of the drive to be an inch or so higher than the edges so as to help run off the sides.

I hope that helped some. I've been out of this for about 9 months now, and don't remember as much as I'd like. /forums/images/graemlins/waytogo.gif

4. ### Stickseler3/4 ton status

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Re: Inspired by \'Fumes concrete thread, a concrete question

5. ### newyorkin1 ton status

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Re: Inspired by \'Fumes concrete thread, a concrete question

Landsmasher, I'm definately hiring someone to do it, this is way too complicated for me to do myself. One of the guys I talked to was asking me stuff and I was like "kjjjjjserwoeiu??" I am going to try to use some of the extra to re-cement my back stoop myself, though.

Skratch, thanks for that info, too!

Stickseler, I've been eyeing this, but no way is my tax return going to be that much!

6. ### skratch1/2 ton status

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Re: Inspired by \'Fumes concrete thread, a concrete question

You can do that yourself it's easy!

We did a ton of those earlier this year, but only in garages.
Um small water heater and a small pump to keep the fluid flowing at a constant rate.
Guy used some special flexible tubing but said most anything that can take the heat and pressure will work ok.
They claim it uses some special liquid, but when the guy told me what it was, it's RV antifreeze! Exactly the same chemical makeup /forums/images/graemlins/histerical.gif
I'm not sure what the proper mix was but once the tubing was laid out across the wire mesh they tied it to the mesh as well and pressurized the lines while we poured onto it. That way the lines didn't collapse.
All in all it seemed easy enough and when we build a house I'm doing my garage and parking slab with it. /forums/images/graemlins/waytogo.gif

I'd look into doing it in a garage, but I don't know about a full drive though.
/forums/images/graemlins/yikes.gif man that system is expensive!

And the type with liquid lines doesn't require a special mix of concrete that is BS to get you buy their system.
A ton of the stuff on there about the Hydronic systems is BS. I've done about 10 myself this last year and a lot of what they say on there isn't true at all!

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