Expert: Dan Griffin - 10/9/2009

Question
Concrete was poured for a 10ftx23ft addition with a continous pour including a 6ftx21ft porch. Within 24 hours, wood for the construction was delivered. The wood was dumped on the front edge of the new porch which shook the house. The edge was chipped in several places. About a two weeks later a crack developed about a foot away from the edge going about 3 ft to the front door. The contractor says the crack is from settling, not damage from the wood hitting it. How can I tell if the porch structure has been compromised and how can the chips be repaired. The entire addition has now been built including a roof over the porch with columns and railings.

Answer
Debbie, it always so frustrating when things like this happen.  I do agree with your builder that the lumber delivery was not the cause of the crack from what I can tell without seeing it.  It doesn't change the fact the crack should not have happened if the concrete was poured and reinforced properly with adequate contraction joints.  Sometimes, even with every precaution and effort concrete has a will of its own.  Contraction, expansion, and construction joints in concrete are designed to provide a straight line for the concrete to crack rather than taking off on its own.  The concrete's shape determines much of this issue - concrete likes to be square, so rectangles will usually break.  Sidewalks are an easy example, a 5' wide walk will have a joint about every 5'.

From what you tell, I would not be concerned about the structural integrity of the porch.  I assume the concrete had an edger run on the porch edge that gave it a rounded edge with a bit more of a finished look.  This is what has chips in it I expect.  I don't know of a way to repair without the repair showing.  There are patching concretes and epoxy products that will stick just fine, but they will show as a different color.  There are some products that could be applied to the entire porch so it would all be one color and also cover the crack.