Greenhouses, Sheds and Sun Rooms - Using existing sunroom AL frame as "studs" ?

Hey gang,

We have a 20+ year-old sunroom whose windows are all losing their gas seals, sweating and streaking, and leaking from about 10 different places, at one point running behind the drywall and causing serious mold. I've got all that drywall pulled out and will need to seal the cinderblock base wall, but now I'm thinking instead of tearing the entire structure down and building a wooden 2x4 frame for a new structure, could I just use the existing metal frame (I'm not sure what kind of metal it is but it's thick, strong, and hard:)? Has anyone ever done this themselves, or have any advice?

The existing metal frame is stronger than hell and seems to be well-attached to the house; the leakage is all in the dried-up gaskets around the windows, and as the windows lose their gas they are sweating inside and leaving a god-awful stain. The frame itself seems sturdy and is already there; why couldn't I just machine-screw an exterior onto the thing and put drywall right up on the inside?

Any thoughts?

Thanks!!!

-c

I know where you're coming from and think it's a good idea. But...

It'll be a lot of trouble, I think. You'll probably need to build a wood frame inside (furring at least) just to have insulation, wires, prefab windows, etc. And on the outside, what you clad the walls with may be a pain to install on arbitrarily spaced metal. There are future weaknesses too, like the fact wood will swell and contract seasonally, while the metal frame does not, and dissimilar metal corrosion between galvanised or steel fasteners and the (I assume aluminum) frame.

But don't pay a dump fee - a scrapyard will buy your aluminum if it's mostly clear of foreign materials.