I am in the process of doing major remodel in my main BR...one of the things I would like to do but don't know if it is possible is to move one of the registers about 2 feet.
I have an unfinished basement so it seems like an easy job except that the ductwork is all running parallel to the floor joists and I don't see a way to simply re-route the ductwork without cutting through the joist and I know you mustn't cut 6inch hole which would in effect break the joist.

Any ideas how to route it? are there some sort of reducers so maybe I can go from 6 inch to 1 inch through the joist and then back to 6 inch ?

I don't know...just wondering if there is any easy way...short of running a whole new ductwork and close the existing one.

Thanks!

 

You can't neck it down to a smaller size to go through the joist and then neck it back up; the airflow will be severely restricted.

Does the duct run back to a large rectangular duct hanging down from the joists and running perpendicular to the joists? This is common. If so, it's fairly easy to move the duct down a joist bay or two by cutting a new opening in the rectangular duct in the correct joist bay, and blocking off the old opening.

There are a couple of specialized tools that make this easier, so you might be better off calling an HVAC co. to have them move it. If there's easy basement access it won't cost you much.

 

I know you didn't mean it as such but thank you for the belly laugh. If you were able to reduce a 6 inch duct down to 1 inch you might as well just dead end it and forget it as you would get almost no air through that restriction.

You have a couple of options. The easiest would be to use fittings to turn the existing duct down, either directly down or at a 45[SUP]o[/SUP] angle in the direction you want to move the register, add another 45[SUP]o[/SUP] elbow to run under the floor joists and then angle back up to a register boot at the desired location. The additional elbows will somewhat decrease the airflow but probably not enough to cause any problems. Another option is to reroute the duct all the way back to the plenum or supply duct using another joist bay. A third option would be to lower the duct so it will run under the joists. Obviously this last option will reduce headroom in that area of the basement and may not be feasible.

 

Reducing a supply air duct is never a good idea. If you have a beam that is perpendicular to the main duct you can simply cut in a new register starting collar in the desired bay (joist area). Especially if the basement is unfinished. If you desire to finish the basement it becomes necessary to increase slightly the size of a sofit to conceal the new pipes. It is also possible to eliminate the duct all together if it is a small room, if not a booster fan could be placed on one of the remaining ducts to increase air flow. It would be important to seal the new duct works to prevent whistling.