siding. When you remove the old siding, you will see the wood sheeting that covered the frame. Tyvek® air barrier can be used here by taping it to exposed wall sheeting or parts of the current smooth siding. The air barrier works the same way as a vapor barrier: all joints need to be well taped for consistent prevention of wind penetration.

Check our article on Stopping Air Leakage if your interior wall does not need to be upgraded. You can use either a piece of polyethylene film or a few layers of latex paint on drywall that has been well sealed to form a vapor barrier. This combination of an external air barrier with latex paint makes the best air leakage sealant in the construction market.