You have to adjust for the size of bags used and for the footings.bledito - 10-23-2013 at 04:16 PM
google concrete calculatordurrelllrobert - 10-23-2013 at 04:42 PM
a 94 lb. bag of cement is 1 cubic foot of bulk material. For a 3/4" maximum coarse aggregate, the mixture would be 1 part portland cement, 2 1/2 parts
sand, 2 1/2 parts coarse aggregate, and 1/2 part water. So this mixture fills 6 cubic ft. (water doesn't count) and your slab requires 69 - 1/3 cubic
ft for a 4" thickness. You need to buy eleven 94 lb bags.woody with a view - 10-23-2013 at 04:50 PM
add 5 bags for the thickened edges, and just in case.Santiago - 10-23-2013 at 05:04 PM
Sigh, I was told 4 or 5 and got 8 as it didn't seem right to me. 94 pounds is a lot heavier than I remember......woody with a view - 10-23-2013 at 05:12 PM
it takes about 2.5-3 bags to mix into a full wheel barrow. look at the area and you can figger pretty close.
4 or 5? one more trip and you're golden!liknbaja127 - 10-23-2013 at 06:55 PM
Bob is right on the cement, but you do need the sand and rock to mix with
the cement!Justbozo - 10-23-2013 at 08:36 PM
Last winter my mason was slinging mud for 6 weeks and never needed more than 3 bags
...at a time!!!
Man that was a lot of trips!larryC - 10-24-2013 at 07:22 AM
I used 250 bags to pour my garage slab and walk way around the garage. Ponsonia can go get more if he runs out during your job.
Larryakshadow - 10-24-2013 at 08:05 AM
Quote:
Originally posted by Santiago
Sigh, I was told 4 or 5 and got 8 as it didn't seem right to me. 94 pounds is a lot heavier than I remember......
Maybe it is because you are using Mexican bags. at least in San Felipe they are 50 k bags which means they weigh 110 lbs
one more trip and you're golden!