View Full Version : Driveway & Garage Floor Prep

07-13-2007, 10:52 AM
I am in the process of removing a driveway and garage floor. The driveway is completely removed and the garage floor is about 1/3 out. I am trying to research the process of prep & pouring cement slabs so I have some Idea of what I am talking about when interviewing contractors for the job. I have found most of the information I need on the web and forums but have found little on the prep before the pour. What do I need under the cement as far as compacting, type of dirt, sand, gravel, do I need a vapor barrier etc. I find this somewhat strange since all the sites I visit say this is the most important part of the process but none of them go into much detail. Any help would be appreciated.

07-13-2007, 09:08 PM
floor prep is the basis for all floors using concrete. your basic floor is dug out to a depth you want. sand is next placed and compacted. a coarse gravel is then levelled out on the surface and again compacted. poly is spread out and re-bar screening is placed. order concrete by the yard and a certain "slump." by slump is meant the amount of concrete (portland cement, sand and aggregate) necessary to slump down for the pour. A slump cone is used. it is a form shaped in a cone, large base and a two inch opening at the top. a sample of the mix is trowelled into the slump cone, the cone being lifted and the level measured. if it drops 2 inches then the mix is good for a 3000 lb test when it cures. lesser slumps yield a higher mix pounds per square inch.

07-16-2007, 10:41 AM
Is the depth of the sand and gravel standard or is it determined by other factors? if standard what is the standard. Also how do you determine the centers for the re-bar grid. Do you need re-bar for both floor and driveway? Also what size re-bar do you use, Is it the same for floor and driveway? What is the thickness of the poly. Is wire mesh exceptable for
use instead of Rebar?

I know I am getting into specifics but I want to know what I am talking about when interviewing contractors.

07-16-2007, 04:40 PM
In general for a driveway or garage use a metal mesh screen - 6 inch square with 3/16" or 1/4" wire. The slab can be a mere 4 inches thick. Once the pour is in, use a vibrator to settle the aggragate and a hook to embed the screen about half way. just reach in with the hook and pull up on the screen about half way and un hook from it. go to another area and do it again. for the four inch slab, you really don't need a vibrator just whack the concrete with a 24 inch wood float. a slab like for a roadway is about a foot or a foot and a half thick with 1/2" rebar - go to your web browser and type in concrete slump.

12-20-2007, 08:27 PM
I need to know if you are familiar with a product called Jewel Stone-Self Leveling. I have a garage floor that either settled when it was poured or just never finished smooth. The worse part is right as you step of the stairs into the garage, the floor at the bottom of the stairs gets a 1 inch deep puddle there from the snow melting off of the car. My idea is to poor this Jewel Stone in this area to get rid of the low area & to color the Jewel Stone so it will math the existing area of concrete. What are you thoughts on this?

Thank you,

12-20-2007, 10:27 PM
I read the article and it seems very good especially the jewel stone plus! The feature I like the best is it's color ability! I may never go back to levelastic. I don't know how much it is but maybe you can check. Hayzee.