AVION Travel Trailers

We are redoing the bed frame and will need to extend the air duct thats under it. I searches and haven't found a 4" square duct. Is there a supplier or is this a manufacturing out of whatever I can find at a hardware store? I don't have a metal brake or anything

Many heating and cooling contractors have fabrication shops. I've used them on past projects.

Thanks, will check with the guys who do our house HVAC

How about transition adapters that convert square duct to round, then back again? I would think 4" round duct is more commercially available than the cost of fabricating square.

Yea, that would be better especially since we changed our plans for the bed size/frame and simply extending the duct wouldn't work anyway. But I haven't found a square to round adapter in 4" in my searches

Maybe this? https://www.amazon.com/Spectre-Performa ... B0035GS6OS

Here is a way to get from square to round. The ceiling collar would have to be bent to conform to the square duct.
For $10, I would give it a try.


https://www.homedepot.com/p/Master-Flow ... /100146818

https://www.homedepot.com/p/Master-Flow ... 124671-_-N&