Published on August 17th, 2013 | by Henri1
Crack between sidewalk and foundation comes back yearly
Q. There is a crack between the house foundation and the sidewalk. I keep filling this crack with cement almost every year but it comes back again. A contractor told me that there is nothing that can be done about it. The problem is that I see moisture on the foundation walls inside the basement. Any advice, please?
A. There is obviously seasonal movement that breaks down your repair. It sounds to me as if your sidewalk is slanted toward the house foundation so any rain water gets into the crack and wets your basement wall.
The ultimate solution is to have the sidewalk redone to slant away from the foundation. This can be done by adding a new layer of concrete (if your sidewalk is concrete) or covering it with brick pavers or flagstones, or by removing it and starting all over. A potential problem with covering an existing concrete or other masonry sidewalk is what happens if there are any steps to the house, etc. An experienced masonry contractor should be able to advise you and make the necessary corrections.
However, if the slant is minimal and you do not, or cannot easily, make the changes to the sidewalk – and the crack is small enough — you could try this: Thoroughly clean the crack as deep as you can. Carefully insert in it a backer rod of the right size without breaking its skin so that the depth of the crack left for caulking is half the size of its width. Buy polyurethane caulking (nothing else) and caulk the crack with it. You can buy backer rods and polyurethane caulking from firms specializing in construction supplies.by