Should I insulate duct work in basement and crawlspace

[Morganza]

I added a bedroom/bath to my house a few years ago. The room stays cold in winter and warm in summer. The high efficiency HVAC system is new and quite robust for the house overall. The unfinished part of the basement and the crawl space are insulated and the temperature is now running about 7 to 8 degrees cooler than the rest of the house. 74 upstairs, 67 in basement/crawlspace. There is probably around 100' of various sizes of ductwork exposed in the unfinished part of the basement and the crawl space. There is also an HVAC vent blowing into the unfinished basement, next to the crawlspace. I'm wondering if it would be worthwhile to wrap the duct work, or would I not gain much by doing so. I'm also looking at a wall heater for the bedroom but I want to consider the duct work insulation first.
Thanks for any comments.
Morgan

[FordMan59]

Maybe this will help you make the determination. https://www.achrnews.com/articles/13...nsulate-or-not

[Morganza]

This is fantastic. Thank you.

[FordMan59]

Personally I think you'd benefit from insulation on the duct work but I don't know what the payback time will be. Let us know what you figure out. If you've got say a 50* temperature difference from the air outside the duct work to the air inside there has to be quite a bit of heat/cooling loss.

I live in a double wide mobile home where the duct work is inside the belly of the home surrounded by insulation. A few years ago I was sitting in my recliner one night and kept feeling cold air coming from somewhere and got to checking and it was coming up through the floor register beside my chair. I don't use the electric furnace because I can heat cheaper with a Monitor heater. Since I don't use the electric furnace I covered all the registers with heavy duty radiant barrier foil held in place by magnets and I no longer feel cold air coming up through the registers. When spring comes I just remove the radiant barrier foil and use the a/c as normal.