Why does my window let air in?

Air passes through worn, compressed seals, poorly adjusted hardware, a sash that no longer seats, or an install perimeter that has become porous. It is not always “the whole window” that is defective.

Repair or replace

Sometimes an adjustment or new seals are enough. If the frame is warped, the PVC is tired, or the sealed unit is at end of life, replacement is more honest.