I am in the process of putting together a freestanding "roof" over my welding table and parts of my backyard. A cover as you will. Awning. Sun shade. Pole barn with no side walls. This is to provide shade during the summer months and some rain protection during the winter months. It will be open on all for sides with a dirt floor, of course. I plan on putting my 4x8 steel welding bench under it on one end, perhaps at the other end the table and radial arm saw and the planer and I can extend it a bit to be able to work on machine tools or drive a vehicle partially under it for service and repair. This being California..snow is not normally an issue I live in an unincorporated area of the county. Things are pretty lax regulation wise in this particular area. Shrug.
The big issue is utilizing the materials I have on hand with minimal cash outlay. Seriously big issue. Most important issue.
I have a good quantity of 16' long 4x8s and 11 joints of 3" pipe, 11 feet long. I have 50 pieces of 5" C channel, about 4' long. The timbers came from an old building that was torn down and are well aged and quite dry.
Because of the layout of my yard, and placement of septic tank and vertical dry well, sinking the posts into the ground is possible, but Id rather make the thing free standing, so it could be disassembled and moved at a later date if access to the septic tank and dry well is needed. If I concrete them into the ground...I cant bring in a rig to repunch the dry well (which Ill have to do before long). If I construct this properly, I should be able to simply stick an eye bolt in each corner, and hoist the entire thing with a hydrocrane and simply move it over some distance. Also, built free standing..I shouldnt need a building permit in my area. Or..can get away with it... There are lots of these things around here, most welded from pipe and used by weekend mechanics and so forth.
A friend brought me the pipe, cut to 11 feet. A bit long for freestanding, but perfect for sinking into the ground.
My plan was..was to use 1' sections of the C channel, with the C facing upwards, with a pipe leg welded into it as a foot. The other end would have a 1' section of C channel facing up, welded to the top of each pipe leg. The 4x6 will set inside the channel perfectly and may be secured via a couple lag bolts from the bottom.
Some opinions are solicited....
How high should I make the roof? 7'? 8' 9'? Too high and I loose the shade effect and the rain blows under it.
Ill need to cut off the pipe, so this is pretty important.
How big should I really make this beast? Bigger the better? I will probably need to be able to hoist it to move it with a hydrocrane.
Should I make it 16' x 16' square? Assume I can orient it in any direction. Should I make it rectangular? Id rather not cut down any of the timbers if I can avoid it, but...shrug. The area I have available is aprox 50' wide by 50' deep and still remain close to the house and power, etc.
How many posts do I need to support a 16x16 square flat topped "roof" made of 4x8s 16' long. Obviously 1 on each corner..but do I need to put a post every 8'? Will those 4x8s sag much with a 16' span? I figure I need to put at least one timber down the middle of the "roof" to allow an 8' span for nailing the roofing to. Probably corrigated sheet metal laid on 2x4s on tie plates nailed to the timbers. Will a 4' joist be sufficent for a simple sheetmetal roof? or do I need to go every 2 feet? I actually dont know what sizes corrugated sheet metal comes in. and what clear span is appropriate.
Is there another product that would be similar in cost that would be better for this purpose? Id love to be able to scround an old gas station overhead...but no luck so far and I need to do this ASAP. As I have the materials of the basic frame, I will need to use a tarp as the roof until I can scrounge up some roof material, or afford to buy some sheets of whatever.
My plan is to bolt the corners together using a single 3x3" steel angle about 6" long vertically inside each butted corner and tied to each beam with a chunk of all thread drilled through the 4" thickness of the beam, and bolted inside and out, rather than using lag bolts. Id be concerned about lifting the whole thing if it was only lag bolted together. I figure that the whole thing may go 2000 lbs if its
16x16 feet square, including the 3" pipe legs and timbers.If I took a pair of 1' chunks of that C channel, and cut them on a 45' angle, and turned them upside down in a welded L shape, I could weld the posts to the bottom, then secure the post brackets to the corner with lag bolts. 2 in each beam 8" apart. The timbers would be resting on top of the Ls and then lag bolted from the bottom.
Would this be stiff enough to not need diagnal braces from the posts to the beams? There will be little if any side loading, except for the odd wind gust.
Any suggestions would be appreciated.
Gunner, who can build a house to code...but is having a bit of a problem doing this critter.
"At the core of liberalism is the spoiled child - miserable, as all spoiled children are, unsatisfied, demanding, ill-disciplined, despotic and useless. Liberalism is a philosphy of sniveling brats." -- P.J. O'Rourke