OT: lightweight roof

I have a puzzle to figure out. I want to scab together a temporary lean-to for the winter, just some rickety shack I can throw up in a week or two before the snow flies. I priced 2x4s and the cheapest plywood sheets at the local lumberyard and figure that I can do 4 walls of a 16x24x16 building for about 400-500 dollars.I figure I can assemble the walls as 8x16 panels on the ground and stand 'em up with a loader, bolting it together as I go. My design doesn't really account for a door yet but I just started thinking about this.

But a 2x4 frame isn't super heavy so I need to think of a relatively lightweight roof that's tough enough to handle whatever snow won't run off.

I am hoping to seal this structure up enough to park a woodstove in the corner for at least enough heat to not need gloves all the time. Even if I figure on laying plywood sheets above the rafters that won't add a lot to the cost but that would be flat enough the snow or rain wouldn't run off and that would increase the weight dramatically. So it needs to have some sort of roof to make the snow/rain go off.

Dan. You can read my post on same type of questions I asked a couple of days ago. LOts of great advice on the awnsers I got. The suggestion made was MENTAL ROOF. Wouldn"t put plywood on the inside of the interior of the roof if there was a wood heater to be added as a heat source. Could be a danger of fire. I would suggest Dry wall for the inside roof. The thiner the better, Could staple insulation before dry wall goes on. Just a suggestion. I"m sure you will get a lot of GREAT INFORMATION FROM UP COMMING RESPONSES>
LUCK ON YOUR PROJECT. LOU

I will promise that if you use thin sheet rock on the ceiling you will regret it as it will begin to sag after a while!

Not sure if I understood correctly, but it sounds like you're using conventional 2x4 wall framing with plywood over the 2x's for the walls?
If so, even with the 2x4's at 24" o.c. you've basically got typical house framing for the walls. That should support most roof systems just fine.
Now for the rafters... if you're going 16 ft, 2x8s would be about the minimum or it will sag over time. 2x4's have a hard time supporting their own weight over that span. Not only that, but the quality of lumber for 16 ft lengths isn't that great until you get into 2x8's. 2x8's are also usually a better grade of lumber - i.e. a structural grade.
Keep your rafters at 24" o.c., lined up with the studs below, and 1/2" plywood sheathing is fine - be just like your house roof.
Possibly a cheaper route if you can find it is some old insulated panels - usually 2 to 3" thick rigid foam with a thin plywood or other type board on each side. span these at 4' o.c. (but don't walk on them) and it should hold. 24" o.c. is better.
Some items to consider:
Most of your heat loss will be through the roof in any design.
The steeper the roof slope, the less snow load/weight.
Ultra cheap/ugly route?
Check with a local signage shop - they usually have old 4x8 plywood signs laying around. Lumber yards also have 4x8 sheets they couldn't sell for various reasons that they will sell very cheap.
Good luck.

You should worry more about the sky falling than a 2 x 4 =16 inches on center studded wall with plywood being the weakest link.

Before ya get too far price out a carport.. they are the fastest and cheapest way to get quick shelter and in most areas they aren't taxable. Normally you can save big $$ by enclosing the side and end walls yourself.. Make sure it is the square tubing if snow load is a concern. The round tube ones tend to sag under load.

A neighbor up here lived in one with a camper and a woodstove all winter long for two years.. with nothing but a green tarp for a door.

What other options do you have for supplies (sawmill?)? Just helped a guy put up some rafters made of 1x6's nailed together with 2" blocks (doubled 1x6's) as spacers. Gave him a 4x6 rafter that is stronger than a 2x6. Set 1 meter oc and and covered w/ 1" boards and roll roofing. Sides were sawmill slabs on a building that needed a little security and tarps on two shelters. Corner posts, stringers, and side framing was 4-6 inch pine logs (real easy to get in our area). We put up 2 13'x 20' 3 sided (tarp) shelters and a 13'x13' slab walled w/ door and the cost was 200 bucks tops... Of course wood prices could be different for you.

Dave
to keep the posts from rotting, we used galvanized holders that drove 3' in the ground.

Hi Dan,

A building built upon skids that is screwed together is consider a portable temporary building therefor not taxed in most states. It just has to "appear" that it's on skids too any inspector. Put your concrete pilings behind the skid rails, out of sight out of mind!

I just called last week, Lowes sells 4ftx8ftx2" styrofoam, $20/sh, 1" was $10sh.

I would take a serious look at using 1/2 solid cedar wood T&G for siding. Use a thin coat of butyl caulking between each T&G joint as well as the lapp ends too the framing, as this would make a air tight seal at all joints with no off gassing that plywood has.

You do the same for the roofing then spray/roll the roof with bedliner sealer.

Use sheet rock screws as there the cheapest and hold well in wood. Very easy too counter-sink as the screws are driven in.

T_Bone

I was technically thinking 24 inch centers.