Expert: Bruce E. Johnson - 8/12/2010

Question
Hi Bruce, I have a problem with water seeping into my basement. It only seeps in during a rain storm. The parging on the outside basement wall is breaking up and needs to be repaired. I suspect that the rain is getting in through the  broken parging. Note it is above the basement concrete so that part of the house wood frame is exposed and this could be where the rain is getting in and going down the wall. So, for my first step, I am planning on repairing the parging. My question then is:  can you suggest how or what to use for cement parging that would water proof the repair.

Thank you for your help.

walter

Answer
Hi walter, cement is not water proof.  Your parging work may be necessary to fix cracks and other defects but when that work is done you need a good paint and caulk for your waterproofing.  Elastomeric paints are recommended for superior waterproofing results but the walls need to be clean and dry and a good primer made specially for these paints is needed to help it adhere to the wall.  Also, your foundation or footing drains have a lot to do with foundation leaks. Make sure your footing drains are not clogged where they dump out if you can find the ends of them.  A roto rooter type company can help determine if the footing drains have been compromised and need cleaning out.  There are also companies with camera equipment that can look at the inside of your footing drains to see if they are clear and working.  A good foundation mastic coating is your next step to keeping the underground walls from leaking but this requires exposing the walls and recoating them.  I hope this information helps please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com