Metal or Lumber

[arizonatruck]

I'm debating on what to use to build my camper.<br><br>I know how to work with lumber and it tends to not be as affected by temperature as much as metal.<br><br>Metal seems to hold up better and can very possibly maximize internal space, at least above the bed rails.&nbsp; Being able to use 2x2 square tubing instead of 4x4 wood.&nbsp; The problem could possibly be electrical dangers like if the insulation on wiring becomes thin, as well as the walls not really being all that able to take a beating without warping or completely opening.&nbsp; It also needs welding and riveting.<br><br>I am leaning towards wood, but sometimes metal seems good.<br><br>Any Ideas of where to get decent lumber or wood for the project that doesn't cost a lot of money.&nbsp; A lot of the wood at the home improvement stores seem like more and more of it is warped, even at the store, even in the deserts of az.<br><br>

 

[daminc]

wood would be lighter, I would think

 

[user 423]

Do you mean for the framing or for the whole thing including roof, siding? Wood is going to be heavier and in most cases you need to keep the weight down. Where would you use 4x4's?!&nbsp; That's overkill on a camper, even a large one. Older travel trailers are framed out with 2x2's and strength is added by the skin and interior paneling.

 

[RJCooper]

Being a carpenter since I can remember I will say this, I love wood, the natural look, the easy of working with it, but metal is the way to go for strength and longevity. Metal does not have to be welded, there is as many bolts if not more in the bridges you cross as welds. Many of the PEB (Pre Engineered Buildings) that house powerhouse turbines, etc are bolted. There is a legion of Teardrop Campers running around on bolt up trailer.

Metal studs and a good carpenter are straighter, the elements don't effect the metal as much as wood. Wood is drastically effected by temperature, humidity and the like.

Just some food for thought.

What are the commercial campers, trailers and caps made with? What does everyone look for in a trailer? Wood rot!

 

[daminc]

how about aluminum for the frame<br><br>

 

[RJCooper]

The cost of aluminum would be high.&nbsp; <br><br>Metal if done right is strong.&nbsp; Don't think you need 1/8" to 1/4" wall steel for it to be strong either.&nbsp; Put up many a light gauge wall and with panels on each side with the right amount of screws holding it on, it's like a brick wall.

 

[arizonatruck]

Sorry, I meant 2x4's not 4x4's.

 

[Willy]

&nbsp;One thing to remember about metal is that it conducts heat, both into and out of your vehicle's interior, whereas wood actually has an R-value and doesn't compromise your insulation to as great an extent. ..Willy.

 

[RJCooper]

@Willy, no offense, but your inside a metal vessel as is, the couple (maybe) of cubic feet of wood is not going to offset that.&nbsp; A cabin or cordwood, yes, but not a vessel.

 

[Willy]

&nbsp;.. but I'm inside an <em>insulated</em> metal vessel. Whatever breaks the contiguity of my insulation allows heat transfer, Which can mean lines of condensation on the ceiling/walls during the winter (and wasting fuel to heat the exterior), and hot 'bars' radiating heat into my rig during the summer. I've experienced both these phenomena first-hand. ..Willy.&nbsp;

 

[RJCooper]

Yes and your vessel is still metal.&nbsp; You are not getting a R19 value out any van/trailer wall.&nbsp; At best you may get a real R value of 7-9 with 2" rigid.&nbsp; I know, I know it is rated for 15-20, but have spent 6 years helping teach the LEED's class at the hall, we thermoscoped many a different structure.&nbsp; Metal being a sum what green building product we worked on the issues of metal framing.&nbsp; In one test, we found metal to conduct heat transfer up to 300 times that of wood.&nbsp; Proving your point right?&nbsp; <br><br>But, when the rigid insulation is cut and fitted inside the c section of the metal stud, now it is better than Douglas fir or most framing lumber.&nbsp; No one should be using batt<span style="font-size: small;"> insulation on their vans as this is just asking for mold and wetness.&nbsp; <br><br>That condensation you where talking about, it is still there, just inside of your outside metal walls.&nbsp; We did these same test with large refrigerated warehouse panels.&nbsp; The old panelized systems used wood for studs.&nbsp; The new systems are more efficient and use metal studs, the difference is the new systems have structural rigid panels covering both inside and outside the panels making a rigid bridge between the two temperature extremes.&nbsp; <br><br>Anyhow, if it were me, I would undercoat or Rhino line the inside of the exterior wall, metal stud with rigid insulation.&nbsp; Preferring the foil faced over straight Styrofoam or Blue Board, just for reflective properties.&nbsp; <br><br>Metal studs are about 1/5th the weight too.&nbsp; Hope this helps.</span>

 

[James AKA Lynx]

In the long run, MILES!!!, the stress of the road will take major problems. Build it with metal and weld&nbsp; preferred over lots of screws. IT will last much longer. <br><br>James AKA Lynx

 

[Willy]

&nbsp;Well, I don't have problems with condensation on the inside of my exterior walls cuz, and you'll find other posts here regarding this, I have an interior vapor barrier. Also, as per consensus, no 'pink fibreglass.. just white (expanded polystyrene) with the bonded VBL facing, one side radiant.&nbsp;<br><br>&nbsp;I have no doubt that the solution you've described could have a better R-value than straight through wood, but there are 2 caveats, one being if the same inner/outer cladding was implemented using wood instead of metal, what would the R-value be and, 2nd, what is the overall thickness of said walls. <br><br>&nbsp;One nice aspect of wood is the ease of tying together both the inner and outer skins, via the wood studs, thus making both structural members without fancy, and oft&nbsp; enough failure prone if not done right, bonding techniques, kinda like automobiles with unibody construction vs. body-on-frame. It would be interesting to see a comparison done between the 2 systems, with an identical wall thickness, but using 1x2's on edge (like many campers I've seen), or 1x3's on edge. ..Willy.

 

[user 423]

If I ever make the switch from a van to a PU, I would explore 'foamie' building techniques that use 1" or 2" thick polystyrene foam,canvas,Gorilla Glue and paint to build a large shell for the bed. Easy to work with and very lightweight. I would probably add 1x2's and paneling on the inside to add strength. Instead of canvas and glue, maybe use FRP for the exterior. R-value wouldn't be important as I'd be using the shell for storage while towing a TT.

 

[Willy]

&nbsp;I'd seriously look into the wood frame with ballistic nylon/polyurethane coated outer skin construction. They make sea kayaks using this method, and they're insanely tough and light. With foam panels between the ribs/studs and an inner wood/Coroplast or whatever skin, It would make for a well insulated and extremely robust/light structure. ..Willy.&nbsp;

 

[rokguy]

<EM><STRONG><SPAN style="COLOR: #888888">One of my trucks is steel framed one is wood. I find the wooden one actually warmer in winter but this is mainly down to the size, the wooden one is built lght using epoxied marine ply and aluminium&nbsp;with not much framing timbers involved. I constructed this sleeper along lightweight modern boatbuilding principles (similar to the West system) along with the aluminium/timber truck tray for carrying upto 2.5T of granite on the back.</SPAN></STRONG></EM><BR><EM><STRONG><SPAN style="COLOR: #888888">The wooden/alloy sleeper and tray has&nbsp;shown no movement or damage considering what I've been&nbsp;carrying since&nbsp;I built it in 2009.</SPAN></STRONG></EM><BR><EM><STRONG><SPAN style="COLOR: #888888">Medium duty commercial truck trays here in Alloy only or steel are either to light (bend or crack) or steel to heavy and chip and rust ot. My tray&nbsp;I built&nbsp;has a&nbsp;sacrificial ply layer which takes the stone nicely but can be replaced easily.</SPAN></STRONG></EM><BR><EM><STRONG><SPAN style="COLOR: #888888">The trucks tare weight is lighter now than when I bought it with a fibreglass pantec on it. Man that was heavy.</SPAN></STRONG></EM><BR><EM><STRONG><SPAN style="COLOR: #888888">To answer the question wood is a nicer material to work with and keeping it light using modern methods is a plus.</SPAN></STRONG></EM><BR><EM><STRONG><SPAN style="COLOR: #888888">Geoff<BR><IMG class=bbc_img src="http://stonemasoncarver.com/sitebuilder/images/littlpod2.roof_done_looking_at_back-266x209.jpg" rel="lightbox"><BR><BR>More pics are here<BR><A href="http://stonemasoncarver.com/rocguy" rel=nofollow target=_blank>http://stonemasoncarver.com/rocguy</A><BR></SPAN></STRONG></EM>

 

[IGBT]

We are building our camper using a metal frame (steel) with 2 inches of polyisocyanurate rigid foil faced foam.&nbsp; Everywhere there is at least one inch of foam between the steel frame and the interior...2 inches between the steel studs.&nbsp; Well, except the floor because we used 2x1 steel there.&nbsp; Thus the foam is only between the studs there but we do have 3/4" plywood over the studs/foam in the floor which should provide some thermal isolation.<br><br>The actual framing was pretty easy....just cut, position, tack weld, check, weld, done.&nbsp; Over a 11 foot section we were&nbsp;out of square&nbsp;by 1/64".&nbsp; Try that with wood <img class="emoticon bbc_img" src="/images/boards/smilies/smile.gif"><br><br>

 

[Willy]

&nbsp;Used to frame/build houses with my dad and.. not hard to keep things 'square'. Nice thing about wood is that, if ya make a mistake, it's pretty easy to fix. ..Willy.

 

[IGBT]

Wood is easy to fix if you split it while driving in a screw.&nbsp; Just have to fill it with wood glue, clamp, and wait a few hours.<br><br>Steel you don't have to fix because it doesn't split when you drive in a screw <img class="emoticon bbc_img" src="/images/boards/smilies/smile.gif"><br><br>

 

[Zil]

Wood is easier to fit to the compound curves of a van. The metal studs used for building constuction are fine for squared surfaces, but take much of their strength from what is sheathing them. I would not use 2x4 but a good quality 2x2 or even 1x2 depending on the suport from the van walls. I built a very serviceable folding bed and "kitchen" using 12x1 pine boards to fit a VW van.