A sill plate runs over the foundation of the house. If it is not sealed properly, then a lot of cold air can enter the house unnecessarily. It must be sealed properly and made air tight. Follow these steps to repair a drafty sill plate with by installing sill plate foam.
Step 1 - Locate the Sill Plate
The sill plate can be set in the basement of the house. It is placed over the foundation of the house. Sometimes it is covered with plastic. Locate the sill plate and check for cold air.
Step 2 - Using the Foam
Push small pieces of foam which is cut into square blocks between the sill plate and the foundation. It is easier to install the foam where the joints are perpendicular to the sill plate. In places where the joints are parallel, push the foam harder.
Step 3 - Caulking the Joint
Once the foam is in place, use caulk to secure the gap between the concrete foundation and the sill plate. If the gap is large, use a foam rod, then apply caulk on the top and bottom of the foam rod.