Concrete handmixing versus pumping

[A]

I got a bid from a contractor to add concrete to my crawlspace.

He indicated he would use 5/8 minus gravel and pump in the concrete, when he did the bidding. After we signed the contract he went into the space and now claims that pumping it in will not work because the pump guys will charge 150 extra per hour of extra length of hose and that that the extra He said he can have his guys cart in buckets of concrete which sounds to me a) very labor intensive b) wont be consistent. c) the concrete layer will be very thing as they might be tempted to take shortcut since it is appears to be so laborious

Its a 1500 sq foot crawlspace. How much concrete would he need- I shudder to think of how many buckets they are going to have to haul in.

Is this a red flag ? Should I insist on the initial agreement and ask him to get the pump and not do it manually. he also grumbled about the finishing time- saying he will need to hurry up with the finishing and it wont be so good if he hires a pump.

How much concrete would one need for a 1500 sq foot basement ? Thanks Ani

[Charles Schuler]

[Joseph Meehan]

Yea, it is labor intensive. I did mine about the same area, one 40 lb bag at a time. It took months and that was just me and a iffy back.

Think of it this way, it is a craw space. It need not be a work of art. It need not be perfect.

Mine is not a work of art, but it does keep the chipmunks out, which was the reason I put it in.

[Harry K]

You will need a lot if it is a 4" pour. Some one posted a calculatore for you but the calulation is simple. 1500 ft square, divide by 1/3 =

500 cu ft, divide by 27 = 19 yards.

He may not be talking about handmixing. He would probably order up a pre-mix load.

Harry K

[thetiler]

That's a couple of truckloads of concrete. Not too likely they'll carry it in buckets. Maybe it could be done with wheelbarrows if the truck chutes can be directed into the crawl space and men could drive wheelbarrows in there. Pumping is very efficient and pretty fast. Sounds like your guy is goofy- I suspect he is not experienced or a professional at this if he changes his mind so much. A professional would have looked at your job and determined for sure what needed to be done.

P.S. I drove a cement truck for 18 months a long time ago so have a little experience with this. The real cement finishers were expert and knew exactly what they were doing- and the fly-by-nights, handymen and homeowners usually struggled to figure things out.

thetiler

A wrote:

[Malcolm Hoar]

Which is probably around 1500 bucket loads.

At least this project will have some pretty good entertainment value ;-)

[Joseph Meehan]

I agree with your comments and BTW, hat's off to all those drivers. My limited personal experience is that they are well informed, and very helpful.

[Harry K]

Uhuh. Even more so if he tries hand mixing. I gave some thought to continueing the figurren to see how many sacks of premix but it would be a rediculous number.

Harry K

[Ralph Mowery]

I needed about a yard to use as the base of an antenna tower. Had 50 bags delivered and rented a mixer that would probalby take 2 bage at a time but I only mixed one bag at a time. That was all I thought I could handle with the mixer and get it to pour in the holw. It took about 4 to 5 hours to mix that up and just dump it in the hole next to the mixer. Used 43 bags in that hole. About what I caculated. Thought I would use 45. I needed the other bags for the guy wire posts and only had one 80 lb bag left over out of the 50.

I would hate to think of the time and effort it would take to haul 10 to 20 yards of the stuff. Also the cost of the bags is much more than the ready mix in the truck, especially if you get more than about 3 or 4 yards. Think a guy at work got 3 or 4 yards delivered in the mixer truck for what I had in the yard I mixed. Where I wanted the cement a truck could not get to and did not need the other 3 yards to make up the minimum ammount they charge you for if you use it or not for the delivery.

[bloomingdale]

First of all, not being able to see your particular jobsite makes it difficult to weigh in on this one. What kind of access is there to this space?

Based on what you've said, and being a concrete contractor, I cannot imagine carting in 19 cubic yards of concrete. F.Y.I. - a concrete truck usually holds 10 cubic yards, so you are looking at 2 truck loads.

It sounds to me like your contractor doesn't have much experience with pump trucks, especially the cost involved. Using a pump truck does not make the concrete more difficult to finish, where as taking several hours to cart in

19 yards of concrete will make it much more difficult to place and finish. The benefit of a pump truck is that the concrete can be placed much faster, thus giving the finishers much more time to do their job.

Hope this helps.

[Harry K]

For a yard or more it is worth checking with them. If you get -real- lucky, they will have a truck delivering somewhere in your vicinity and may split a load.

Harry K