how much concrete?

[herb white]

I want to pour a 4 x 8 slab four inches thick at the entrance to a garden shed.Will someone please tell me how many 80lb sacks of concrete I will need? Thanks for any reply

[Mayayana]

|I want to pour a 4 x 8 slab four inches thick at the entrance to a garden shed.Will someone please tell me how many 80lb sacks of concrete I will need?

I think it's something like 2/3 cubic foot per bag, but it's on the bag. you can just check when you buy it.

[Ralph Mowery]

You can calculate it here.

About 18 of the 80 lb bags. Plan on an hour or two to mix it up as once you start, you will need to finish the job. I am sure you are planning on putting in some rebar or wire to help hold it together.

[Terry Coombs]

Look in the yellow pages for a you-haul-it concrete outlet . Beats the hell outta mixing that much concrete if you're doing it by hand . And you need 4' x 8' x 1/3' divided by 27 = .391 cubic yards - less than a half a yard but you'll probably have to buy a half .

[Ralph Mowery]

He is also looking at about 1500 lb of dry mix in the bags. I needed about a yard of concreter for an antenna tower base. I used about 45 of the 80 lb bags for that. Rented a small mixer for about $ 35 to mix it up in. Where I wanted it was about 100 feet from where a truck could get and they want to charge a lot for bring out a small batch. I did have 50 bags delivered for a small extra charge. Total cost was about the same as for 3 or 4 yards delivered by truck, but I only needed one. Took several hours to mix it all up and just dump it in a hole.

If you can get 40 pound bags for close to the same price I recommend that as the larger bags will wear you out.

[Tony Hwang]

Hi, Ralph Are you a HAM?

[Pico Rico]

I have not seen 40 pound bags but I buy 60 pounds rather than 80 or 90 pounds, as they are easier to handle.

This reply was referring to a "haul it yourself" purchase, where they give you a tilt hopper trailer for you to tow home. I don't know the pricing these days, but cheaper than having a truck deliver, and easier than mixing your own (depending on quantity and wheel barrow mileage). But if it is an antenna raising party, you should have some help, eh?

[hah]

[snip]

Strangely, that calculator accepts negative dimensions. We now have proof of the existence of anticoncrete.

[snip]

[Ralph Mowery]

Yes, you can look me up at qrz.com, Call of KU4PT.

I just have the top of the 60 foot tower with the antennas on it showing in the pix.

I did all the work of putting up that tower myself except some people on the ground with some ropes pulling the tower sections and antenna up.

[nestork]

4 feet X 8 feet X 1/3 of a foot = about 10 cubic feet.

On the bag it will tell you the yield per bag will be about a half cubic foot per bag, or something like that.

So, you're looking at about 20 bags.

I'd buy 25 just so that you have extra just in case you need more. You can always return the bags you don't open.

[Class Clown]

Right about now you are probably wishing you paid attention in school, huh? I would be so embarrassed if I couldn't solve a simple algebra problem that a 7th or 8th grader would be able to.

[philoÂÂ]

I had a similar sized project but figured it would be a real PITA to lug that many bags.

I found a "Metro Mini-Mix" that specializes in small batches and had them pour me a yard of cement. It cost a little more than doing it myself but it was a hell of a lot easier.

[Doug Miller]

nestork wrote in news: [e-mail]:

Closer to 11: 32/3 = 10 2/3

2/3 cubic feet per bag

32/3 cf / 2/3 cf per bag = 16 bags

If he follows your advice, he's going to be returning at least a quarter ton of concrete.

[Tony Hwang]

Hi, My call is VE6CGX, old call is HM1AY. Remind me of Gin pole. My neighborhood restricts antenna height and such a hassle to have a decent tower. Just getting by with multi band vertical. Still CW is my main mode. I love QRP brick radio, QRP Plus.

[HomeGuy]

In every CF of concrete there will be anywhere from 5.5 to 8.5 lbs of water (2/3 to 1 gallon of water).

The slab in question will need 10.66 CF or about 1480 lbs of dry incredients. This would be 16 bags if each bag weighed 92.5 lbs.

I question the need for a 4" slab. The slab could easily be 3" or even

2.5" if the slab will never be exposed to vehicular weight.

Anyone in a position to transport and mix 1500 lbs of concrete could probably just as easily obtain bulk sand, stone and cement and mix them together during batching. The cost savings would be significant, as pre-mixed bagged concrete is much more expensive than buying bulk sand and stone from a quarry or landscape materials retailer.

Your average small mixer (3 cf drum) can mix about 200 lbs worth of wet concrete per batch (about 1.35 cf) and if you get really good at it you can mix and pour a batch in about 20 minutes if you have all incredients lined up in buckets ready to dump into the mixer. A 4" slab would require about 7.75 batches and take about 2.5 hours to mix and place at minimum with 2 people using a small 3-cf drum mixer.

[bob haller]

your far better off getting your concrete delivered in a mix truck.

price it both ways, bags are expensive. although get a couple helpers for finishing

[Ralph Mowery]

He needs less than 1 yard. Around here they want to charge a minimum of a price of about 3 or 4 yards even if you need less.

For me several years back it would have cost about as much for one yard either way, bags or truck delivered. I just could not get a truck where I wanted it and did not want to do the wheelborrow thing.

[Ralph Mowery]

Several years ago when the economy was doing well a fellow at work needed 3 or 4 yards and one company he contacted said they could not sell him any at the time as it was is somewhat of a short supply and they were servicing their regular contractors first. He did find another place that was about 5 % higher that delivered to him.