A wall sleeve is a metal or plastic tube installed through an exterior wall to create a sealed penetration for air conditioner line sets, electrical cables, or drainage pipes. It prevents air leakage, moisture infiltration, and structural damage at the wall penetration point. Proper installation with caulking and insulation is critical for energy efficiency and building integrity.
Technical Specifications
Wall sleeves typically measure 4-6 inches in diameter for through-wall AC units and 2-3 inches for ductless line sets. They consist of galvanized steel or PVC construction. Installation requires drilling accurate holes, securing the sleeve flush with the wall surface, and sealing gaps with polyurethane caulk and expanding foam. Sleeves should slope slightly outward to prevent water pooling.
Installation Standards
Building codes require wall sleeves for all exterior penetrations. Sleeves must extend fully through wall cavities without gaps. Caulking must remain flexible and weatherproof, with annual inspection recommended in freeze-thaw climates.
Common Applications
Wall sleeves accommodate through-wall AC units, ductless mini-split line sets, and window unit installations. They protect against thermal bridging and air infiltration, reducing heating and cooling losses by 5-10 percent.