Calculating cubic yards for concrete pad.

[trof]

I am absolutely astounded by how much WRONG information is on the web about this.
Many sites discuss calculating SQUARE yards.
Ready-mix trucks don't carry SQUARE yards, they carry CUBIC ones.

Here's how you do it.
Measure length times width of pad to be poured, in feet.
If irregular shaped (as mine will be), sketch it out and divide it into measurable sections.
It ain't that hard.

For a 4" slab, multiply your total sq. ft. total by 0.33.
4" = 1/3 foot.
Now you have the total cubic FEET.
Take that number and divide it by 27.
There are 27 cubic feet in a cubic yard.
Now you have the total cubic yards needed.

BTW, concrete suppliers usually talk 'yards'.
The 'cubic' is understood.
:-)

[txlibdem]

1. Right you are

Also, don't forget to over-estimate a bit. It's easy to break apart excess concrete later on but sooo difficult to make do with less than you need. If you're pouring a foundation it would be a good idea to also build forms for the sidewalk or patio, in sections, then if there is any excess concrete you an use it for that.

[trof]

2. I'm pretty close to a full truck load for the project.

8.5 yards here.
Ripping out an old ground-level wood deck I built in 1994 and replacing it with a much larger concrete deck.

The old wood deck looks pretty shabby and has a family of armadillos tunneled under it.
:-(

If I'm a l-e-e-t-l-e under I'll finish up with sackrete.

[txlibdem]

3. A family of Armadillos?

I woulda shit a brick if I'd seen that!

:-)

[Wash. state Desk Jet]

4. that's funny !

Here's another way ,take a bag of 60 or 80 lb. sackrete. The bag says what it is in cubic. the length and width of the bag is equal to itself as is for a 4 '" slab. OK,so now you take the measurement of that bag plus depth as is and measure away . Just imagine placing one bag in front of another until you full the the area with bags of sackrite -that will all add up to a 4"slab! You can do that with one bag of sackrite and yer tape measure.Or you can measure the bag at the store! Area plus depth !As many bags as it adds up to is yer cubic measurement !
Again the cubic measurement is on the bag !

For about 25 bucks you can buy a contractor calculator that does conversions ! Since you like to build, you should have one of those !Slip yer area measurement in there plus depth than flip the slider button over to concrete ! Bingo yer there !

I don't remember if formulas came before or after blueprint reading ! Somewhere in there in trade math !

[Warpy]

5. Hey, food on the table!

It's a frequent item on the menu in much of South America and according to both Bourdain and Zimmern, quite tasty.

Skunks would have been another matter, entirely. You can evict those with mothballs, I've done it. It's just a little funny to realize there are some stenches that even offend skunks.

[trud]

6. I like skunks

I am happy to see them mosey up on my deck and eat the peanuts I leave out for them.

[jmowreader]

7. You missed one small but very significant calculation

You got the cubic yards in your slab...but for the cubic yards you need to order, add 10 percent because the bottom of the hole is never flat--unless it is a huge slab, then 5 percent overage should be fine.