[Portland Brian]

Do I need to have sheet metal duct and boot all the way to the register/vent, or can i drop the duct into a wall space and use insulation and sheet rock to channel the air to the register?

 

[hvac benny]

Not for supply air. If you are concerned about not having enough room to run a pipe up or down a 2x4 wall, you can use 3x8 oval pipe, which is basically ovalled 6" pipe. To transition to regular round pipe at either end you will need an oval end/angle/universal boot, depending on which direction you need to go. A sheet metal shop should have these.

 

[E-TEK]

My home has fresh air return ducts without metal inserts - they just go through joist spaces. Is that found often? Should one try to put metal liners in?

 

[thehvacguy]

you dont need sheet metal necessarily on your return. a common practice is to place the furnace on a non insulated wooden stand. being fully enclosed, you cut in a vent on the other side of the wall. for your supply you would use what is called a riser pipe. they make it 2 by 10, 12, 14, or 16. it is designed for this application. make sure you get it insulated!

 

[E-TEK]

Sorry to hi-jack again, but since you're looking at this thread - can I ask you a question? I need to move 2 heater ducts 3 feet each. One has to go through 2 or 3 joists (on an angle). Can I cut and sister them? Should I use a 2" pipe to minimize the cut? The other has to go along the joists, but I wonder. do you just cut the floor boards and patch the hole, or try to remove and replace them as complete pieces? Thanks.

 

[hvac benny]

Sorry to hi-jack again, but since you're looking at this thread - can I ask you a question? I need to move 2 heater ducts 3 feet each. One has to go through 2 or 3 joists (on an angle). Can I cut and sister them? Should I use a 2" pipe to minimize the cut? The other has to go along the joists, but I wonder. do you just cut the floor boards and patch the hole, or try to remove and replace them as complete pieces? Thanks.

1. You can drill though your joists provided they are tji joists and you follow their guidelines. If they are regular 2x10 joists then no can do.

2. 2" pipe will only move enough cfm's to heat a large shoe box, you'll need to use the same diameter pipe that you currently have.

 

[E-TEK]

So - how would I move that one duct over 2 feet - which is across 2 joists (2x10 type)? The ceiling below is closed in....

 

[hvac benny]

It's kind of hard to see from here, but if you just move to the left a bit... lol:laughing:. Without pictures, or better yet, being there it's pretty difficult to give you any ideas. You may have to drop it below the ceiling and build a drop around it, or move it to a different location in the room. Posting pictures may help, or they may not, but go ahead and post 'em any way :thumbup:

 

[E-TEK]

Thanks very much benny - even without pics you managed to answer my questions!!! Cheers!