Buildings can settle and shift over time, creating gaps and cracks around doors, windows and vents that can leak cooled or heated air from inside. This can cause your HVAC system to work harder to maintain a consistent indoor temperature, leading to higher energy costs. Sealing your building envelope with caulk, spray foam and flashing can prevent air infiltration, yielding significant energy savings and dramatically improving occupant comfort. These measures can be self-installed or installed by a contractor.