How much slope should I put in a roof?

Im at the point where Im getting ready to put a roof on my "awning" in the back yard. Its a 16' x 16' freestandinging gizmo that will cover my welding Stuff, a place to work on vehicles, and so forth. Lots of similar units around here are flat roofed, but as it appears that we may be getting some rain for the next couple years, Id like to put a small slope on it. How much slope should I put in a 8' span, just to get rid of rain water? 4" 3"?

Gunner

"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

Reply to
Gunner
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This kind of depends what kind of roofing you are planning to use. The cheapest way is with tin but that tends to leak over time. The next cheapest is roll roofing where you need to torch down the seams. Then you can use comp shingles.

As far as the slope goes, the tin you can get by with a 1:12 pitch The roll roofing with a torch don edge you can go 2:12 or 3:12 for comp shingles give yourself at least a 4:12.

I think I would go with the comp and a 4:12 pitch. Be sure to consider wind load as you have a big sail catching the wind. bolt the sucker down.

Reply to
Roger Shoaf

My shop is 1/4" per foot. I water leveled it and subtracted 3.75" 15' away. Make it a little more if its not really flat , mine is two layers of 3/4 plywood.

Reply to
Sunworshipper

Do they give away plywood where you live?

Reply to
Jim Stewart

I built a house with 6 in 12 and concrete tiles. It got slippery when wet, but I already learned when I sipped off the frozen plywood on the first course.

If I build another, it will be 4 >Im at the point where Im getting ready to put a roof on my "awning" in

Reply to
Clark Magnuson

I've got a lean-to on the back of the house, and it clears water just fine with a 6" drop over 10 feet.

Dave Hinz

Reply to
Dave Hinz

"Standard" roof slopes are 4/12, 8/12 and 12/12. Given you are not dealing with snow loads, I would think all of these would be excessive for your application. Maybe 6"? 3-4" is going to be pretty flat. Not that the extra 2" is going to even be a noticable visual difference. How much rain are you talking about? 1/2" over 2 hours at a time or

2"/hr. A light rain will be more forgiving of the flat roof, but long, hard rains will want a steeper roof to facilitate water removal. Just my thoughts. Worth exactly what you paid for 'em.

JW

Reply to
cyberzl1

They did if you knew where to look before 911. The shop cost about $900. Half of that is just concrete. If there was a natural disaster I'd rather be in the shop than my house. Plywood is down right scary now, I bring home some and the neighbors are like vultures. Matter of fact I took apart 2 garage doors and chopped the metal up like firewood yesterday and the neighbor had to come over to see the old rotten 1/2-" plywood.

Had the drill all hooked up and not one screw would come out so I had to rip the plywood off the screws with a crow bar and two hammers at the same time. That reminds me, I need to put all that in my truck for the dump real soon so my kid doesn't get hurt on all that sharp metal.

Oh, the ole beach tent stakes work good. Dig a hole and put in a horizontal stick and string tied to the middle. Read metal horizontal and cable buried. That way Gunner's roof will never take off.

Reply to
Sunworshipper

I should add that this is with steel sheet roofing (the painted stuff with a raised seam every foot; comes in 4' wide sheets). Pole-barn stuff.

Reply to
Dave Hinz

I vote for matching the roof angle on your house. Look better. - GWE

Reply to
Grant Erwin

Mine will be 3/8" plywood on 2' centers. I scrounged up 8 sheets of

3/8s, just plumb full of staples. I think I can get some rolled roofing really cheap.

So far, Ive got $6 in the project. Not counting the electricity to weld the legs to the support members.

The legs are 3 1/2" oilfield pipe and to the bottom of the beams, is

8', 9"

I wanted 8'...but my buddy cut them a bit long, and I shrugged and welded them up.

Ill post a picture or 2, later tonight in the drop box

Ive got 4 more shorter beams (10') and another 6 or 8 11' joints of

3.5" tubing if I want to make another awning..which I might do to cover some Stuff

Gunner

"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

Reply to
Gunner

Bet this is why you wanted a drafting machine... Sorry I learned not to sell my first.

Reply to
Sunworshipper

I must be one of those that they make laws that has to have a percentage of the land absorb rain fall or shall we go as far as sun light...

100% no rain would be cool. How about a funnel roof over the entire property and then sell it ! LOL
Reply to
Sunworshipper

Depending on your roofing material, minimum slope should be 3 in 12. This is for shingles and a lot of metal profiles. If you go to a 1 1/2" tall rib on a metal profile with sealant tape on top of the lapping ribs, I think you can go down to a 1 1 /2" in 12", but that makes me nervous. Of course, I've always lived in rainier climates.

Reply to
Gary Brady

NO SLOPE!!! Everyone should have the wonderfull experience of a flat roof, only better if you were in Ohio.

Reply to
Tom Gardner

Actually no..I never drew a sketch. I had it pictured in my tiny little skull and simply built it the way I pictured it.

Though to be fair..I have had a small bit of experience over the years building things like houses and office/warehouses.

Gunner

"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

Reply to
Gunner

Chuckle..I made it 4" in 8 feet. Looks pretty good. I simply ran the

2x8 ridge board, then stuck on the plywood. Rain is coming so I did a quick and nasty. Next weekend Ill put in the rafters from below using hangers. It may flap like a sail and leak between the sheets during the week,, but its gotta be better than no roof at all.

Gunner

"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

Reply to
Gunner

Ijust finished putting up a steel building for my RV. Bought it in kit form. The factory pitch is 1 in 10.

Steve in Daytom

Reply to
Steve Mellenthin

Don't know how much, but make sure it slopes to the right!

Reply to
Fred R

Depending on your roof covering - shingles should be no less than 2" in 12" - roll roofing (if well sealed) could be *almost* flat. Ken.

Reply to
Ken Sterling

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