[AIVC, Air infiltration and ventilation glossary, 1992]:a) The fitting of a strip of flexible material to seal a joint between a movable component and its seating of the application of mastic sealants to seal infiltration openings. The strip is attached to one edge and excludes air by pressing tightly against the other. b) Fixing a piece of material to stop a draught passing through the joints of a closed component (such as a door or window).(see caulking)