Expert: Bruce E. Johnson - 9/2/2008

Question
Bruce,
We recently had a porch enclosed and we have a leak a corner around the floor.  It looks like it is coming in under the 2x4 and the concrete floor.  We have put flashing all around the floor and used silicon caulking too but we still have the leak.  Can you help?

Answer
Hi Debbie and Steve, Silicon is not a good caulk for this application. For one thing unless the slab and the wood are completely dry silicon will not bond.  When the walls were framed was there a bead of caulking under the wall also?  And why is water getting up to and under the wall?  Do you have positive drainage away from the slab?  Is there a sprinkler that shoots water directly at the house in this area?  If there is no way for the water to reach the slab then really no water will get in under the wall.  Is it possible that the leak is coming from above and running down the inside of the wall and only showing up on the floor?  And how is the flashing installed?  Could it be that the flashing is actually catching the water and trapping it behind so that it seeps under the wall?  I'm kind of at a loss as to what is causing your problem based on the description.  Maybe you can go over some of my questions and write again. Sincerely bruce e johnson