Steel studs vs Wood studs in box truck conversion

[morkani]

(I hope this is the right forum for the framing inside the box truck)
Metal doesn't flex and as I understand wood does. Is this a problem in a box truck conversion? Or does the box typically stay rigid anyway? I really like the mold proofing & lighter weight benefits.
Rust I'll have to worry about because I plan to have full heating & air conditioning. But I'm hoping that yellow foam insulation which forms a vapor barrier will be sufficient?
(I don't plan to "off road" much. it'll be a 26' likely)
Thanks

 

[highdesertranger]

metal flexes too, the thinner the metal the more flex.

is it a problem? depends

does the box stay rigid? depends on what type of box you have, some do some don't.

highdesertranger

 

[riptorn]

40 years with steel studs here, 2x2 would be ideal. if your worried about rust other things will have that problem before the studs. put a thin foam strip (a thermal break) at the floor & ceiling track and outer wall studs and box it's self. You can buy much heavier studs (12ga) than you can get at the big box stores , 
First fasten top & bottom track , cut studs '' 1/4 shorter raise ''1/8 off floor that will help with flex and squeaks . 
Studs do have a top and bottom , cut same end on all (top) keep your runners in line , a small pair of c clamp stile vice scrips will make wall building much easier.
Steel studs were first developed for ships

 

[barleyguy]

I helped build the interior layer of my garage with steel studs a few years ago. I really like them. Some advantages I like:

1. They go together with screws and a drill rather than nails. I'm better with a drill than a hammer. This also tends to pull the frame into the proper shape. Short version is I think they're easier. Someone experienced building with wood may disagree.

2. You can insulate in the "pockets" of steel studs. Since they are a "U" shape, you can tuck insulation all throughout the structure of them.

3. They are easy to attach lengthwise for lengths (or heights) greater than 8 feet. You can overlap the "U" shape and screw them together.

4. I _think_ they are lighter, though it could depend on the type of wood they are being compared to.

 

[highdesertranger]

you can use screws on wood too, just saying. in fact nails other than brads should not be used in a vehicle build. highdesertranger

 

[tx2sturgis]

Building with wood studs means less 'thermal bridging'. Wood tends to insulate against the transfer of heat rather than conduct it, like metal does.

Along those lines, its less likely to have a DC wire short out due to vibration and chaffing against the metal..and yes, you can use metal or plastic conduit with metal studs...but that means you have increased cost and complexity of the build.

I tend to use either or both, usually wood and aluminum, depending on what makes sense in the particular situation.

 

[riptorn]

'thermal bridging'
''1/4 foam strips , 
 wire short out due to vibration and chaffing against the metal metal or plastic conduit with metal studs...but that means you have increased cost and complexity of the build.
Conduit is unnecessary over kill , below is just one example of plastic insulator made for running lose wires safely through metal studs , you could also run your PEX (plumbing) through it. Also if you put a full plywood (and maybe vinyl) floor down first , That would act as a thermal brake at the floor.

https://www.menards.com/main/electr...ngs-25-bag/sb13-25/p-1444424266703-c-9538.htm

 

[tx2sturgis]

1/4 foam strips 
 
... below is just one example of plastic insulator made for running lose wires safely through metal studs , you could also run your PEX (plumbing) through it. Also if you put a full plywood (and maybe vinyl) floor down first , That would act as a thermal brake at the floor.

But all of those things you mention increase the cost and complexity of the build, as I said they would. 

Not a lot. I get it. Just pointing out that a few other items might need to be bought and put in place to protect the wiring when framing with steel, or aluminum for that matter. 

And, even if you put in foam barriers, you may still get thermal bridging with the fasteners: bolts, screws, whatever, as they connect the framing member to the exterior body or frame components.

And yeah, as mentioned by HDR....no nails in structural joints if using wood...Torx or star-drive TEK construction screws or similar work well.

 

[sushidog]

Why do you need any studs? I had an Aliner which is built entirely out of SIPs (Structural Insulated Panels) with no studs whatsoever. The walls were made of a thin outer skin of aluminum, and a thin 1/8" plywood inner skin vacuum bonded to a 1" thick foam core. The cabinets and bathroom walls were made this way too. It is structurally rigid and extremely lightweight. Here's an example of SIPS you can buy: http://www.walkincooler.us/insulated-panels/ But you could make your own. Glue your insulation to the metal wall and glue thin plywood sheeting directly to the insulation on to the inside. Use thick enough foam and you could hang meat in there in the summer with a 6,000 btu ac. My Aliner had a 5,000 btu Ac which was sufficient, and it only had 1" of insulation.

Good info here on gluing polyiso and van builds: https://sprinter-source.com/forums/showthread.php?49932-Glue-Polyiso-to-Metal-and-Plywood

Chip