Floor Joist Panning

It also can be nailed on the bottom of floor joists to convert floor joist cavities to a duct run.

Floor joist panning.

Female end allows interlocking of multiple pieces for long runs. This product is proudly made in the usa using galvanized steel construction for durability and rust prevention. Other articles where pan joist system is discussed. A two way version of pan joists called the waffle slab uses prefabricated hollow sheet metal domes to create a grid pattern of voids in a solid floor slab saving.

So far the only option i have found was to use hard pipe. Used to seal the underside of the floor joist space to create a return air duct. Master flow 16 in. Galvanized panning is used to seal the underside of a joist space.

Joist panning can be installed between wall studs to enclose the stud cavity creating a duct run. Joist panning lining seems to still be popular. However a have read in a few places that joist panning is difficult to seal and can pull air from unconditioned spaces. Using floor joists as return ducts by panning can cause leakage because negative pressure in the cavity will draw air from the outside into the cavity through the construction joints of the rim area at the end of the joist cavity.

Still commonly used is the panned floor joist. It can be cut to size to suit a variety of applications. 16 in width is equal to the distance of joist spacing allowing the panning to be nailed or screwed directly into the wood.