here is teh plan froa simple garden shed being installed in the back yard up along teh property line. It slopes from front to back and I have noi Idea how to determine the angle to cut the birds mouth and plumb cut on each end.
I can post deminsiosn if it will help any.
Rafters will be 2×6, it is about 3/ 12 pitch
any help or direction woudl be most beneficial.
http://img.photobucket.com/albums/v648/Mntngoat/Home%20Improvement/DSC00472.jpg
ML
Smart construction decisions and material choices can significantly improve occupant safety and survival in the event of a fire in the home.
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Dig into cutting-edge approaches and decades of proven solutions with total access to our experts and tradespeople.
Start Free Trial NowGet instant access to the latest developments in green building, research, and reports from the field.
Start Free Trial Now
Replies
Assuming that you are putting on a straight shed roof, I would measure the distance between the two top plates (inside edge on high front wall to outside edge on the lower back wall) and that's how far apart to space the bird's mouth notches.
I set up my framing square (3/12 pitch in your case) to cut the notches so that the horizontal cut of the bird's mouth is the width of the top plate so it will sit entirely on the plate.
I add on as much length for the overhangs as I want beyond the bird's mouth notches. The ends just get cut off at your 3/12 pitch angle.
Hope this helps.
If the walls are in place, just tack a board to the outside of a wall and mark it. Then use it as a pattern to cut the rest.
not really sure what the issue is but if kyle's suggestion works it would be worth your time to put your speed square on your template rafter after you've cut it per his suggestion and you'll probably see the 3/12 line in the "common" section of the speed square. that may help you understand better for the next time. If I've misunderstood the problem my apologies. Also laying some sticks on the ground replicating a 2dimentional view of your roof, although not accurate enough to mark any cuts, can help your brain wrap around the angles. especially with a speed square or better yet a framing square by your side.
______________________________________________
--> measure once / scribble several lines / spend some time figuring out wich scribble / cut the wrong line / get mad
Not a bad framing job so far. I'd put the sheathing on all four walls before starting the roof.
The simplest way to make the rafters fit nicely is to set and hold each one in it's intended place before cutting it. Mark the edge of each wall on the rafter by holding something straight, like a framing square or a short length of 2X4, against the sheathing, next to the rafter. Then lay the straight edge on top of the wall to make a horizontal, level line above it. More about that line later.
You can then mark the plumb cuts on the ends of the first rafter by sliding the rafter up and down until the rafter tails are in line with the edge of the wall, then use your straight edge again, holding it vertically against the wall and draw a vertical line on the rafter.
Back to the saw horses: To find the bird's mouth, move the horizontal lines down to where they are the proper length (3 and 1/2 inches plus the sheathing). You can move the lines using a small piece of sheathing or even a carpenter's pencil to make parallel lines.
Assuming that there's some errors in slab and the wall framing: After cutting the first rafter, nail it in place. Mark the next rafter in it's intended position, then mark and cut the bird's mouths. Finally, place each succeeding rafter against the first one to mark the end cuts.
This is a very practical method which will give you a decent set of rafters, each one custom fit. The roof lines should be straight.
BTW, it's avisable to add a length of 1X2 to the top outside edge of each rafter, all the way around the roof. This will give the roof's drip edge a little overhang, protecting the painted surfaces from constant runoff.
just cut the first one and then move it along the wall to see if it will fit every where. no sense in climbing up and down the ladder any more then you need to.______________________________________________
--> measure once / scribble several lines / spend some time figuring out wich scribble / cut the wrong line / get mad
And what if it doesn't fit? Looking at the photo, I suspect that everything is enough out of tolerance to make it necessary to custom fit each rafter. That's why I spent a half hour, writing up those instructions.
Thanks HVC sounds easier than I thought it would be.ML
You'll do fine. If you run into anything peculiar, just let us know. There's enough peculiar people on BT, including our hosts, to answer almost anything.
BTW, the shed looks to be quite close to the property lines. Do you know what the legal set backs are?
Anything less than 120 SF does not require a permit, if it requires a permit 5' setbacks are necessary. I'm at 2' I should send you some pictures of others in our neighborhood, one a 2 story barn type shed not more than 6" from teh fences. sticks up over the top of the fence a good 8' You think sheeting the walls is necessary, prior to stucco?ML
That's a strange set back law, at least for permanent structures such as you describe. Hey...whaddo I know? If it's common practice, I'd probably do it the same way.
You think sheeting the walls is necessary, prior to stucco?
I didn't anticipate a stucco job so no sheathing is required.
Only problem is that you've put up the walls without any let-in braces so that's going to take some extra time and effort now. Easiest would be to buy some galvanized steel braces, one for each wall. Hold one in place and mark it. Set the proper depth on your circular saw, then notch out the space for the brace. Watch out for nails.
Actually the city may have an issue with it being semi-permanant, but those cheesy metal sheds everyone keeps throwing up never get moved so portable are they?There is a let in brace on the facing wall I took the picture before I installed it.. Have you ever tried cutting in a brace with the wall standing..... Not recommended.
I will try and get in one fore on the wall facing the block before it is stood this time.ML
As long as you have good relations with your neighbors, you'll probably be O.K on the legality of the shed. I'd just avoid talking about it with anyone in the neighborhood.
I agree about the difficulty and danger of using a circ saw to cut anything other than in a well supported, level position. If that doesn't work out, you could put a 1X4 or 1X6 wood brace on the inside of the wall, without notching.
That ain't no 3/12 from what I can see.
I'd be addding a ridge and two plane it, put the ridge towards teh high wall about a 1/3rd bach, and about 2-2and a half feet high..that gives ya much better slope, and then shingles will work a lot better.
Unless I am toatally not seeing the wall heights rightly.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
MSL,
You came to us a bit late. If you would have asked before you framed the walls, I would have suggested that you cut an angle on the tops of the studs....then no birdsmouths would be needed, just straight rafters. Seems like thats the main reason to put a shed roof on a freestanding structure.
But you got it built so we can move on. Hudson has the method I use (sort of). In a new build, I usually lay out a full scale drawing on the deck or driveway, in remodeling I often use the "guess and check" method. In your case this is easy. You just put a rafter up and use a speed square to draw a line indicating the front and back of the two wall plates. Then draw a line level from the high side using a torpedo level.
BTW: I think you should download and try Google Sketchup before building any more sheds or house additions. Excel is not a drawing program, you'd be better off drawing with a paper and pencil than with Excel. Sketchup is easy as long as you actually take the 30min to watch the first couple tutorials. Once you get the hang of it you will want to tear down that new shed to build a garag-mahal.
GK
I've played with Sketch up a bit just not enough to actually draw anything with it yet. But will be learning it and will use it next time. ML
What are all the dimensions, including front and back wall height? Is that short wall where the door way is supposed to be the 3/12 pitch?
Joe, I took a guess at the 3/12 pitch, ML
What is the height of the front and back wall?
Joe Carola
Edited 11/18/2008 4:52 pm ET by Framer
Peak is 93" low side is 85"ML
What are you planning on using for roofing?Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
Peak is 93" low side is 85"
With the short wall with the door in it at 6' 3-7/8" run and an 8" rise, that gives you a pitch of 1-1/4/12 pitch.
The back wall with a 12' run and an 8" rise gives you a 11/16/12 pitch.
Do you have a height requirement there?
You can make this roof real simple and use a 3/12 or 4/12 pitch for thew whole roof if you want by making a shed roof starting on the 6-3-7/8" wall running back towards the 12' wall and just raise the wall height on the 6' 3-7/8" wall the same as the 9'11" wall.
Or you can make a gable wall with a 3/12 or 4/12 pitch running from the 6' 3-7/8" wall going back to the 12' wall like trapezoid having a valley and hip rafter on the angled wall. Also raising the plate height.
It's easier than it sounds.
Joe Carola
Joe do you have any sketches to help me visually see what i woudl need to do?ML
Here's the roof with a 3/12 shed roof running from the 6' 3-7/8" wall to the 12' wall with the three walls being the same height. I made it 8' by mistake.Joe Carola
Here's the shed with a 3/12 Gable. I didn't draw any overhangs
Joe Carola
Here's the other side of the gable version.
Joe Carola
It's funny - I understand the ground plan is not square, but the 3D views look so OFF! I've been staring at 3D for a couple days here, and that just looks WRONG!
I know it's not.
Forrest
The angled wall for the shed roof just creates a valley with valley jacks. With the gable roof, one side is a valley with valley jacks and the other side is a hip with hip jacks. The 3/12 pitch stay the same for all rafters.
Here's a shot of the shed roof rafters, valley and jacks.Joe Carola
Jim I'm leaning to this one for ease, in order to have an overhang does the valley rafter just get pushed out farther?
A
lso would you just recommend ballooning up the front wall to gain the height required for the 3/12 pitch? ML
Jim I'm leaning to this one for ease, in order to have an overhang does the valley rafter just get pushed out farther?Also would you just recommend ballooning up the front wall to gain the height required for the 3/12 pitch?
ML
Are you talking about the one wAre ith the shed roof?
Joe Carola
yes
You want overhangs off the siders? You also should have one on the front roof over the door. How big?
Joe Carola
I'm leaning towards 12" ML
Here's a shot of the top view of the gable with one side a valley and the other side a hip. 3/12 stays the same.
Joe Carola
It's funny - I understand the ground plan is not square, but the 3D views look so OFF! I've been staring at 3D for a couple days here, and that just looks WRONG!
I know it's not.
The problem is the way he framed the walls. He made the back wall/angled wall 88" and the front wall 93" thinking that was a 3/12 pitch. It's not. To make matters worse, the 12' side makes the pitch almost flat.
Sure he can just nail rafters right on top of what he has and they will all have a slightly different pitch and the roof will have a roll effect to it because every rafter the pitch changes smaller and smaller as the run increases going from 6' 3-7/8" to 12' with an 8" rise.
Hope this makes sense.
Joe Carola
Here's what I've been designing -
View Image
Forrest
Edited 11/19/2008 1:08 pm ET by McDesign
Here's the other side of the shed roof.
Joe Carola
Here was another thread about three years ago with the same shape with different measurements. I thought there was.
http://forums.taunton.com/tp-breaktime/messages?msg=53239.1
Joe Carola
You saw that too?
Looks almost flat.
Edit: Now I wonder if it is indeed built as drawn, must be the new glasses.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
Edited 11/18/2008 4:34 pm ET by Sphere
Sphere your right it is only a 8" rise over the width http://img.photobucket.com/albums/v648/Mntngoat/Home%20Improvement/DSC00472.jpgML
Dude, at 12' wide or so, that is flat as far as I'm concerned. Not no 3/12...
Consider my gable idea, you can get it up enough for a MUCH better plan of attack.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
After rereading your reply I understand what your saying now. whats the minimum pitch for comp shingles?
That magic 3/12 is about what I'd trust, but I did my whole roof with Ice and Water, and cheated the exp. down, and got by on 2.5/12...BUT it is a living house , heated..not a shed. You may be OK at 2/12..but, it's close to being risky.
What you have now, is never gonna fly with shingles. IMO.
I don't know your climate or snow load, but if you put 7/16 Ply or OSB , it's gonna get saggy I'd bet, even with 16" center rafters.
Edit: I see SoCal..so I don't think snow is an issue..LOL
Still, I'd make it steeper, by hook or by crook.
Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
Edited 11/18/2008 5:58 pm ET by Sphere
I could pony up the peak and the 2 rake walls without too much trouble to get a 3/ 12 out of it.ML
I would, it's visually more appealing. IF you have no contraints on height there.
I like the offset ridge, move it toward the front some..might have to dink around to get the "right" look/proportion. Or what I do often for sheds/chicken coops...just use an 8' or 10' 2x4 with the desired overhang in the back, and where ever it dies and at the slope you like, call it good, place the ridge there, then the Front rafters, can be determined ( not the same pitch most likely) and go from there, they may or may not work out to a common cut avail length.
Being as the front is likely shorter, and the front wall is slightly higher, that is where the "A little less than 3/12" would be OK.
What I described works well when there is a greater difference in wall heights ( Think "SALT BOX") and also on even heights..that 8" you have is peculiar, for sure.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
the idea was to keep as low as possible as to not be a issue with the neighbors. Thats just the way it worked out. As you can see the header is tight up against the plate. didn't want a cheesy metal shed but needed someplace to keep the yard equipment.
I hear that, but I also avoid flat roofs whenever possible.Spheramid Enterprises Architectural Woodworks
Repairs, Remodeling, Restorations
They kill Prophets, for Profits.
My first rule of measuring is don't measure if I don't have to. I would rest one joist on top of the walls and scribe it. Then use that one as a template for the rest.
Hope that's helpful. :)
See my work at TedsCarpentry.com
Buy Cheap Tools! BuildersTools.net
set your ridge first. set a block of wood on the opposite plate that is half the thickness of your rafter. pull a string from the top of the ridge first and to the back end of the block of wood. use a t-bevel or speed square to find your angle and measure from the top of the ridge to the back of the block of wood to get the distance from your ridge cut to the back of your birds mouth. add for your soffit and cut the rafters. I've only done used this method twice, so I may goofed something there, but if memory serves me, that is how we did it.
If you can't figure it out from my rambling, look up block and string method on google.