Concrete pad 'do it yourself'?

Question

hi, we need a concrete pad pored, we tried to find a contractor for 2 years, but they are too busy for a small job :(

so now we are thinking of doing it ourselfs (husband and myself), we have no experience and limited knowledge, should we try it? (if you are close to hamilton, ontario, maybe help?) we are so disappointed in contractors right now... we had several coming for a quote and then renegging on us

Answer 1

If you're not perfectionists and don't mind a less than perfect slab, I would go ahead and try it yourselves (assuming this is 10'x10' or something small).  If it's a large slab, don't even mess with it.  

I'll give you the easy way to install concrete.  

1. Prepare the area.  Flatten out the dirt in the area you wan the slab.  Build forms with 2x8 or 2x10 so that the inside of the board is the size of your slab (meaning 10' long x 10' long, if that's your slab size).  The top of the boards should be where you want the top of your slab.  You should have to dig these into the ground a bit.  Hold the boards in place with wooden stakes.  Use a string line to make sure things are straight.  Check to make sure the forms are square by calculating the distance from corner to corner (a^2 + b^2 = c^2) and measuring.  Dig around the inside of the form in about 10" to 12" so that the edges will be at least 8" thick.  The center of the slab should be about 4" thick for any normal purpose.  

2. Once the form work is set up, you need to make sure the soil is compacted properly.  The easy way to do this is to turn a sprinkler on and let it soak the ground for a couple days.  Then turn off the sprinkler and let the ground dry out (at least so it's not muddy).  

3. Prepare rebar (steel reinforcing rod) to run around the thick edges of the slab.  So for a 10x10 slab, bend pieces so that you get 10' straight, then a 90 degree bend, then 10' straight.  I usually use 2 sticks of rebar all the way around the edge of the slab.  I have these off to the side and push them in once the concrete is being poured.  Push them down to the bottom 1/2 of the edge.

4. Order concrete.  You'll 1 cubic yard of concrete will cover 81 sq. ft. at 4" thick.  So calculate accordingly and remember to add another 1'x4" all the way around the perimeter for the thickened edge.  Order the concrete with fiber reinforcement and you won't need to worry about wire mesh or rebar in the middle of the slab.

5.  Pour the concrete.  Wear rubber boots and try not to get too much on you (it can cause chemical burns).  As you pour, get it close to the right height with a hard tine garden rake or a flat shovel.  Then take a straight 2x4 and run it along the top of the forms to get the concrete nicely flattened.

6. Float the concrete.  You should be able to rent a bull float at a local rental place.  It's a big flat piece with a long handle that you can glide over the concrete.  Run it over all of the slab, out to the middle and then back to the edge.  This will flatten the concrete more and make it easier to finish.  

7.  Finish the concrete.  Wait just a bit for the concrete to stiffen up.  Finish the edges if you'd like with an edger (cheap at Home Depot or Lowe's).  I'll assume this is an exterior slab that you would put a slightly rough finish on.  The easy way to do this is to run a broom lightly over the top once the concrete sets up a bit.  If you feel terribly ambitious, float the concrete off with a hand float before you broom it.  By doing so you can wait til it's a bit stiffer and get a nicer finish.  If you want to run with the easy method, just lightly run a broom over it after it's set up a bit.  

8. Cure the concrete.  This is a very important step that many miss.  I wait for the concrete to get fairly hard and then put a sheet of plastic over the concrete (carefully making sure it's very flat).  And then spread sand lightly over the top.  Throw a few boards on the edges of the plastic outside the slab (to hold it down).  And wait a few days (5 to 7 depending on how long you want to wait).  This will ensure a strong concrete.  

9. Pop off the forms, clean up, and enjoy.

Good luck.

Answer 2

I'm a builder in La.  Depends on size, thickness, use of the "pad"  It's not rocket science (have you seen foundation crews?)  so if you have a little bit of common sense you can do it.  Go to a local big box lumber dealer and look at the how to magazine section.... or try online.  Good luck!