Replies

1. 
   DanH | Mar 21, 2012 08:48pm | #1

   If the concrete cracked, it's because it moved in two different directions.  If it moved, it's apt to keep moving.  Therefore you need something that's resiliant.  There are several available concrete caulks and sealers that will work.

   However, for a 1.5" wide crack you probably want something firmer.  One option is to dig it out, fit in an expansion strip, then apply patching cement on both sides.  There are also pourable sealers that get harder than caulk but are still resiliant.

   No doubt others will have other suggestions.

2. 
   florida | Mar 22, 2012 06:51am | #2

   How thick is your slab? How extensie?  I'd guess it's only a couple of inches at best in which case there isn't anything you can repair the cracks with that is going to be permenent.

3. 
   Piffin | Mar 25, 2012 05:31pm | #3

   A slab that old with cracks that big needs to be replaced.

   But if you are looking for a DIY cheap fix, just grout it with a sand mix

4. 
   calvin | Mar 26, 2012 07:45am | #4

   Sand mix should do it

   But you need to clean the edges of the slab and I'd apply concrete glue to them as well.  After you get the patch in, cover with old towells and keep those wet for a few days if you can.

   This method has lasted through a couple seasons of freeze/thaw on the sidewalk up by the neighbors.

5. 
   BobR71 | Apr 04, 2012 08:06pm | #5

   Cracks

   Try a product called Sikaflex. It's a self leveling concrete sealant. If the cracks are deep you will need to use some sort of backer rod. Best thing out there. Sometimes if your lucky you can find at home depot.

1. 
   florida | Apr 06, 2012 08:34pm | #6

   I don't believe Sikaflex is appropriate or affordable for cracks 1 1/2 inches wide, with or without backerod.

6. 
   IdahoDon | Apr 08, 2012 07:52pm | #7

   Concrete is pretty cheap so I vote to tear it out and replace it, but until then I'd clean the cracks well, spray on some moose milk, then use a grout for most of the cracks.