Installing Ductwork In Floor Trusses

To prevent problems use saddles or straps to support at regular intervals 4c 4d follow the manufacturer s instructions but in case they get lost here is a list of best practices for.

Installing ductwork in floor trusses.

Sometimes the best route for a flexible duct run is up and over an obstruction. Return air ducts usually use ceiling joist spaces as the actual duct which then runs back toward the furnace. Make sure not to install joists so they run parallel to and directly under walls where you intend to install ductwork. Adding heat runs in a basement may change the airflow in the ductwork going to other rooms.

The metal connector plates of the trusses can be hazardous to flex duct. With the right tools you can install a return air duct successfully. Figure 3 open web floor trusses with furnace in garage. Run ductwork between floor joists whenever possible and anchor it in place with galvanized hanging straps.

Finally if all else fails drop your pipes and ducts down below the joists and box them in with wood framed. Attach the galvanized hanging straps at 4 foot intervals by hammering them into the. Pulling flex duct across a sharp edge can easily damage the duct. Ducts should be able to run between studs in the wall and then turn into a joist bay the space between two joists.

Install dampers at the registers to adjust airflow. Just be sure to get the sizing sorted out correctly ie a 12x12 duct cannot be replaced by a 3x48 duct same area as there s a lot more friction in the 3x48 but the correction factors for duct shape are surely. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b. Each register should have its own damper that can be accessed for adjustment.

You may be able to work with a wide shallow duct so you can have a broad not too deep soffit for the cross joist duct run. Position bathroom vent fans so the ducts can run parallel to the joists right up to where they exit the house. This also reduces the need and cost for extra bearing posts beams and footings. One way to eliminate this problem would be to ask the truss manufacturer to install.

These joist spaces empty into an actual duct that runs perpendicular to how the joists run and then down into the side of the furnace. Floor trusses have built in openings which can be used to install hvac ductwork plumbing lines and electrical wiring.