Cutting Floor Joists For Ductwork

The hvac should have gone up a wall not laterally under a floor by cutting joists.

Cutting floor joists for ductwork.

I own an old home circa 1919. Proper way to cut a joist and go to images. 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. So in direct correlation to those cut joists are ou.

In the 70 s when the new furnace was installed they cut through the floor joists to run the air ducts. Position bathroom vent fans so the ducts can run parallel to the joists right up to where they exit the house. Here s bob s trick for taping a seam on a pipe that s installed close to the subfloor. But without proper support ducts can develops sags or kinks that reduce airflow 4a 4b.

Sometimes the best route for a flexible duct run is up and over an obstruction. Slide the backing up and over the pipe. To minimize problems with ductwork. If you need to cut through a joist firm up the floor as shown in fig.

Leave backing on the tape on metal ductwork. Tradespeople often need to cut notches or holes in floor and ceiling joists to run pipes ductwork or wires. Attach ductwork that branches off and approaches each vent or register in the house. Use sheet metal duct elbows to work around bends and tin snips to cut the ductwork for a precise fit.

Cut a piece of foil tape to length. Hvac can run parallel to floor joists though and there are code acceptable ways to cut holes into joists but generally those holes are not big enough for hvac ducts only plumbing and electrical. If the ducts are going to be concealed all seams need to be taped or caulked. 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.

Peel off part of the backing.