Expert: Dan Griffin - 4/9/2009

Question
We had our driveway ripped out and repoured last spring. The process was stressful because we had a cold MN spring and had to wait for frost boils to go away and then the mud, etc. We got through the winter without one crack, but now the entire driveway is crumbling. It started with a few "pocks" and now the whole top is crumbling apart. I don't think my contractor did this, I think the cement company gave us bad cement. What can we do now?

Answer
Annette, there are only a few things that will take a top off.

Contractor working the concrete too soon before the bleed water is reabsorbed.

Contractor troweling air entrained concrete.  All exterior concrete should be air entrained.  NO TROWELS.

Contractor adding excessive water to the truck to make it easier to pour.

Contractor/owner failure to cure and seal the original concrete.

Freezing temperatures within the first 3 days and nights.

Bad aggregrate in the design mix (unlikely from a major supplier)

Salt or other deicing product.

All of the above can produce a weak plane in the concrete between the top and the rest of the concrete which may not show until allowing moisture into the top which freezes and pops the top.

Contact your contractor to get his input.  As you can see, there are ot many reasons for the supplier being at fault.  There are a lot of reasons for the contracotr being at fault.  There are topping cements that can be applied if the basic concrete is sound (I think it is) and dthe damage is limited to the top.  If your contractor does not do this type work, seek a "decorative concrete" contractor in your area.