Cutting Floor Joists For Ductwork

Peel off part of the backing.

Cutting floor joists for ductwork.

Position bathroom vent fans so the ducts can run parallel to the joists right up to where they exit the house. I own an old home circa 1919. Proper way to cut a joist and go to images. Cut a piece of foil tape to length.

The hvac should have gone up a wall not laterally under a floor by cutting joists. In the 70 s when the new furnace was installed they cut through the floor joists to run the air ducts. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b. If you need to cut through a joist firm up the floor as shown in fig.

Tradespeople often need to cut notches or holes in floor and ceiling joists to run pipes ductwork or wires. 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. 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. Use sheet metal duct elbows to work around bends and tin snips to cut the ductwork for a precise fit.

Sometimes the best route for a flexible duct run is up and over an obstruction. Sometimes joists are notched at the end where they bear on a wall or sill. Slide the backing up and over the pipe. Attach ductwork that branches off and approaches each vent or register in the house.

Here s bob s trick for taping a seam on a pipe that s installed close to the subfloor. To minimize problems with ductwork. So in direct correlation to those cut joists are ou. 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.

If the ducts are going to be concealed all seams need to be taped or caulked.