Roof joists

[dogneck]

All the walls are up.  I was going to get someone to do the roof, since I'm scared of heights, but they quoted $5500 to do the joists, osb and metal roof, and crib walls.    I'll just have to try to get it done myself, but need to get under roof before winter.
I have the 14x24.   The lower wall is 8' and the upper wall is 10 high.    I calculated the roof slope, but figured 8' on one side then 10' plus 9 1/2 (2x10 joists).  That was wrong.   It's simply 2' difference over 12'.   1.75 to 12 roof pitch.   Pretty bad.   I'll use roll roofing then put metal on top of that.   On the beams, I have to figure the bird cuts.  What simpson is used for this connection.    I guess the 2x10 could go on 24" centers?   

[glenn kangiser]

That is almost a flat roof, dogneck, so you shouldn't have any problem with it other than the fear of heights. 

Could you put scaffold up around it so you wouldn't have to worry about it or build your own staging  out of wood?  I did that on my 12/12 pitch in the area I couldn't get the forklift to.

[dogneck]

I didn't think about any scaffolding.   I was going to use a ladder and put in a few joists.  ropeup the osb and get a section done.  Then go across.

[glenn kangiser]

That would be the quicker way and you will likely feel better about it after getting started and getting a few sheet nailed down.  You could also put up temporary handrails around your work area.  We do that on the big steel buildings I do so no one inadvertently walk off the edge.

I see that people under the  influence on the jobsite have the most accidents.  The cautious un-influenced ones seldom have problems.  Possible but not as likely.

[Redoverfarm]

John have you already purchased the rafter material?  Is there room above your 10' wall to go higher?  Are you using a ledger system to attach to the house?  If you haven't purchased the rafter material and are using a ledger you could increase the higher wall to gain more pitch.  If you have a wall built against your house and have not purchased the rafters you could build a short wall sort of ballon fashion on top of the wall to gain your pitch provided you have the room.  Either of these would require longer rafters.  What is your overhangs(gable included)? You are correct in that in a flatter type roof you should use rolled roofing to ice guard. 

[dogneck]

I cannot go any higher because of a bathroom window.   I am not using a ledger connected to the house.  I've already built a whole 10'  high wall.   I'll just have to go with a flatter roof.     Do you know if that quality roofing in Ona sells  "standing seam" metal roof?   Someone told me that with the flat roof, to either put roll roof down first or use a standing seam metal roof.     I don't see many around here except for commerical applications.   
I emailed to Simpson, but no response yet-  trying to find what connector to use for the roof joists-  (if any needed??)    I was going to have about a 1 ft overhang all around (except where it meets the house).  But I'm having trouble and may not have any overhang at the side walls.   

[MountainDon]

You can use an H1 hurricane connector to tie the rafters to the wall plates. Go to...

http://www.strongtie.com/products/connectors/H.asp

...for info, specs and diagrams.

If I understand your problem with laying out the birdsmouth cuts...  on a shed roof design this is very easy. It may be easier with a helper. Place a rafter across the top of the 10 and 8 ft high walls. At the 10 ft wall use a level or some other straight edge to scribe a line on the rafter at the inside edge of the 10 ft wall top plate. Without moving the rafter then go to the 8 ft high wall and scribe a line on the rafter that lines up with the outside edge of that walls top plate. The wall sheathing should already be installed so this line will be aligned with the outside surface of the sheathing.

Those lines are the "heel" cut for the birdsmouth.

Then using a right angle square you draw the foot cut. The foot cut is usually as wide as the wall top plate. They may be narrower in some circumstances. You can also draw them with the rafter still in place across the wall tops by using a 2x or something as a guide across the top plate.

See drawings below...



I hope this helps.

Roll vs standing seam. Roll roofing will be considerably cheaper than anything else. Metal on top of roll roofing would be overkill IMO. Use double the coverage type of roll roofing with such a low slope. It is best handled in warm weather. Tar the seams well. That should work for many years.

[MountainDon]

I guess the 2x10 could go on 24" centers?   

Depending upon your snow load this would be correct.

There's a calculator at
http://www.awc.org/calculators/span/calc/timbercalcstyle.asp

You enter you lumber type, grade, size, adjust the load and spacing and so on.

[dogneck]

Thanks.   I was going to try the birds cut with using the t-square, but this method seems easier.     I might have to go to 16" centers.   The problem with the calculator is that the wood at home depot and lowes doesn't tell you what grade it is.    Some are marked "stud"      "Top choice"  - what is that? As I was pulling through their 2x4's   I saw crayon color markings on them.  Seems like those with red should have been thrown out- because no one would buy them.  The green mark seems to be the best- less knots and no end splits.   They just put a whole mix in the same bundle.   I can hand pick through it. 

[MountainDon]

HD and Lowe's as well as real lumber yards will sell some lumber marked as 'stud grade", usually 92 5/8, 96 and up to 10 ft. The longer stuff, here at least, is generally marked #2, #2 or better, #2 btr....

When you use the rafter/joist calculator you use the distance between the support points, not the overall length.

Remember if the lumber just makes the cut you'll be better off not "pushing the envelope". Using a closer spacing, greater width, better grade or sme combination will result in a more sturdy structure.

Top Choice is a brand name.

[MountainDon]

If you're cutting the birdsmouth with a circular saw don't overcut, finish the cut with a saber saw, jig saw,....

[Redoverfarm]

dogneck I am not sure about standing seam at Ona.  I think they are in the telephone book.  In regards to their roofing Vs. Standing seam.  There is approximately 7/8" elevation in the ridges that each sheet connect to.  Water would be hard pressed to make that rise.  Not sure what the standing seam elevation is. 

I would spring for the "ice guard" not storm guard.  It is self adhesive and self sealing.  Sort of a rubber like roll.  HD & Lowes normally have it but as I stated one(Ice guard) is far superior.

When you get the first rafter cut correctly set it aside for a pattern.  Use it as your last rafter to install.  Occassionally if the building is out a little keep check on how the birdsmouth is meeting the plate. If it started to develope a gap then just move your pattern on your board to lengthen it after you have made your cut on the house end. 

If you are plumb cutting the tails I usually let them run wild and come back and make the plumb cut after a chalk line to make sure they are all the same distance from the sheeting.  If you pre-cut and one or more is off then your facia will be wavy. Make since.  If you have a bevel square that is what I use.  Set it to the right pitch then using the chalk line at the top you snapped your plumb cut will be right and all the rafters will end at the same point.  Usually do this prior to sheeting as your sheeting should overhang the rafter some. 

[PEG688]

   Purdy good job there guys.

   The OP was to convoluted,  so I let it be. 


  I see ya all have got er figured out for ole Mr. Neck.


   Listen to what they said Dog.

   G/L PEG