Where to Seal Air Duct Leaks with RCD Mastics


Seal Heating  & Cooling Air Ducts With Mastic & Save Energy. Leaking air ducts can be found in attics, crawlspaces, basements, garages, closets, ceilings & walls. Sealing all joints & seams with RCD Mastics will reduce wasted energy, lower monthly energy bills, reduce carbon emissions, and improve indoor air quality & comfort. Seal those areas highlighted in blue with RCD Mastic.


Look For Disconnected Ducts           Seal Cavities Used As Ducts            Air Handler Plenum Connections
Seal Branches With Mastic            Seal Boots With Air Duct Sealant            Seal Joints & Seams With RCD Mastic



♦  Flashlight and/or head lamp with fresh batteries. Check out RCD's hat with built-in head lights.

♦  Attics with no flooring; a work board you can move around that will support your weight and span across two joists.

♦  One gallon pail and two or three caulk tubes of #6 Mastic .

♦  Caulk Gun , Mastic brush and Fin & Plenum Brush.

♦  2-3 pairs of latex throw away gloves (when only your hand will fit).

♦  One roll of Glasscoat mesh.

♦  2-3 cloths and a can of #34 Coil & Fin Cleaner for wiping joints clean before applying mastic and for clean up.

♦  Utility knife and telescoping inspection mirror.

♦  Pliers, screw driver and tin snips (you never know what you’ll run into).


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