Expert: Bruce E. Johnson - 9/25/2010

Question
I had my carport enclosed 25 years ago and yes it sits on a concrete slab. The masonite on the outside is rotten at the bottom and when it rains, water runs in. What can I do to repair this. I will have vinyl siding put on but how can I make sure water will not run under the studs?  

Answer
Hi Debrah, cut the rotted masonite off the bottom of the exterior wall and clean the joint between the bottom plate of the wall and the concrete as good as you can with a steel brush or stiff brush and then caulk that joint with a good urethane sealant.  Replace the masonite (with new material, preferably Hardi backer board instead of masonite) prior to installing the vinyl siding.  If water is building up outside the wall above the bottom plate of the wall then you may need to add a metal flashing that runs up the wall above the water line.  This flashing would have to be caulked into place also prior to the new masonite or hardi backer being installed. I hope this information helps please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com