Hvac Duct Under Floor Joist

Floor joist cavities can make acceptable duct chases for insulated air sealed metal flex or fiberboard ducts.

Hvac duct under floor joist.

I want to avoid a cross over and sofit where a hvac duct loops under a joist into an adjacent cavity see duct jpg. Any ideas would be appreciated. What size pipe would be appropriate. What the installer did here was to screw a piece of sheet metal to the bottom of the joists and attach a duct to it to carry the air back to the hvac system.

Keep in mind due to you are wanting to relocate the duct work you have to take into account that you could end up changing the design of the system overall and may or may not cause problems with air flow. As we look closer here s what we see in this house. See the illustration by the u s. Any structural problems with drilling a 6 hole in a 10 inch rim joist over a poured foundation 9 actual.

Is that a towel in there. Hvac duct options in floor joists. Department of energy below. In this case it s big enough that there s even a joist running right through the middle.

Is there a way to pass through the double stringer. Depends on where the vents are located on the floor above. You would normally run the parallel between the beams or joists and the trunk would stay as close to the middle of the house. 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.

Only approved duct materials such as galvanized steel aluminum fiberglass duct board and flexible duct that meet local code smoke and flame spread criteria must be used. Supply runs off the top within the joist spaces to boot and register. It s right in front of my glass block window. 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.

In the 70 s when the new furnace was installed they cut through the floor joists to run the air ducts. I plan to cut a hole in the rim joist above the foundation and then rout duct under the rest of the joists. The ideal duct layout in your situation would be to run the main supply and return trunks at right angles to the joist direction.