Concrete Floor

[DaveRR]

I'm looking to pour a concrete floor in my basement, and just got my second cost estimate. I've never had any concrete work done before, so I thought maybe some of you could tell me how reasonable this estimate is.

The basement area is 430 sq ft. Part of the floor is already concrete (170 sq ft), and the rest is very coarse sand (native soil). I have already removed enough dirt to (more or less) level the unfinished floor a few inches lower than the finished floor. The foundation walls are dry stacked stone, and entrance to the basement is such that the concrete truck can back right up to the basement stairs. I'm not looking for anything fancy; just a concrete floor with a sump in the corner. Concrete prices here are $90-100 per yard.

The first estimate was $2,200, and the contractor planned on keying the new floor into the old floor. His price is based on 3 full days labor, which doesn't sound right to me. In any case, this is much more than I'm willing to spend.

The second estimate was $1,200, and the contractor plans on pouring a completely new floor, 4" thick with wire mesh. He thinks it will turn out best if the old concrete is removed first. Removal of the old floor is not included in the estimate, because I would do the work myself. I can afford this, but it's still a bit more than I expected.

What do you guys think of this second estimate? Is it reasonable?

Thanks for your help!

 

[Ron25]

My calc's come to about 7.5 cubic yards - @ $100 per and the mesh, your around $800 + in material alone. I'd think it would be worth $400 in labor at least.

Sounds like a deal to me.

 

[JJT]

Are you looking for a nice finished floor? If so, rip out the old and pour a single slab. If headroom isn't an issue, don't rip out the old, just pour over the top.

If looks don't matter, leave the old alone. You will have a joint/crack between the old and the new floors.

 

[EddieWalker]

For labor and materials, I think $1,200 is very reasonable.

I don't know what the existing slab looks like, but since it is your home, I'd think you'd want it to look as nice as possible. Take out what's already there and have one nice slab that you can be proud of.

If you have never busted out slabs before, it really helps to pry it up a little, then break off the pieces with it in the air. When it's flat on the ground, it takes allot of beating. In the air, it breaks off real easy with a sledge hammer.

Have fun,
Eddie

 

[DaveRR]

Thanks very much for the advice, guys!

The floor down there doesn't have to be perfect, but if I'm going to spend the money, I guess it's worth some extra work to make it as nice as possible. I've already removed between 7 and 7.5 yards of dirt down there to level the floor out (two 5-gallon pails at a time), so removing this concrete shouldn't be too bad in comparison.

I was thinking of renting an electric jackhammer, but I'll try lifting the slabs first, like you suggested Eddie. Thanks for the tip!

 

[Syncro]

I was thinking of renting an electric jackhammer.....

Electric jack hammers are useless. If you can't break it out with a sledge as Eddie suggested and absoultely need a jack hammer, then rent a compressor and air hammer. Trouble is though this will produce vibration that may be a problem if the foundation walls are stacked stones. How old is this place anyways??

If the concrete is really old it can sometimes become extremely hard. You may be lucky though if the original mix was weak, and its a pretty good chance from what you describe that the existing slab was probably home made and hopefully shy on cement.

Good luck!

 

[DaveRR]

The house was built in 1870. The inside of the house was pretty much redone just before I bought it, but the basement didn't get any attention.

With energy costs so high this past winter, I'm working on insulating the floors and plumbing. We decided to upgrade the furnace and ductwork, (the current furnace is an OLD oil furnace converted to natural gas) and I figured this would be the perfect time to get a finished concrete floor down there. Plus, the basement is really dry and dusty, and cutting down on that dust might be better on a new furnace.

Anyway, I tried the sledgehammer in a couple places, and the concrete breaks up easily. The solid concrete is only 2-3 inches thick, with a layer of crumbled concrete/stone underneath.

 

[bugstruck]

$1,200.00 reasonable? If you've checked their work history and are comfortable, sign them up before they wake up and realize they quoted you $300.00 for two guys labor for the better part of two days. Wire and poly aren't cheap anymore. Make sure you put down 6mil poly as a vapor barrier. Sand or no, still need it.

Incredible price assuming materials are included. Here, they'd get that much for labor only.

 

[rox]

DaveRR,

It is always so nice when people fill in a little bit of their profile, at least minimully where they are from.

 

[gordon21]

Most areas of the USA now pay $4-$5 per SF for a slab with no problems or special work. You will be getting about a $2200 job for most areas of the country. $1200 sounds like you are dealing with a small contractor skirting various issues such as building permits, workmans comp, etc. Don't get me wrong. I have used these guys in the past and all went well. You just need to make sure whether you are dealing with someone like this or someone dumb who will will figure out out about half way through the job he is not making anything and walk off the job unfinished. Several yards of unfinished concrete in your basement would not be a pretty sight. I highly recommend pulling up the old floor and having one new continous floor with wire mesh and expansion joints next to the walls. It will cost you at least 10-15 hours of your own labor to tear up the old floor. It will be worth it in the long run.

Basic 4000 PSI concrete in Florida is now running $125 yd and is about $100 in western NC. These two areas probably represent the extremes of pricing. Your quote of $1200 is very cheap.