Replies

1. 
   Piffin | Oct 07, 2002 03:47am | #1

   So what is the required live load in your area? and what is the roof pitch?

   As a general idea, the 2x8 @24"OC ought to do you fine but loads in this country range from 15# to 90# in my experience.

   Personally, I would use 2x6@16"oc unless that was inadequate for the load in your home town

   .

   Excellence is its own reward!

1. 
   maneyj | Oct 07, 2002 04:03am | #2

   I agree with piffin on the 16" centers, but then I always believe in overkill.

2. 
   fupcreek | Oct 08, 2002 06:57am | #4

   I appologize, the roof pitch is to be 4/12, with 2'overhang. I am in snow country but far enough down the valley that the big snows miss us in this part of montana.I agree with 16 oc. A friend told me on his similar roof he went with Sprayed foam on under side of sheeting, and then put in r-19, and put in soffet vents to create airflow. I am still wondering if a) this would vent enough or b) it would hold enough heat. He thinks it shoulod act as a cold roof, and the heat stays in. I am planning a partial vaulted ceiling, flattening at around 9-10 feet.Does any of this sound ok or do you offer different opinions?? Thanks

1. 
   Piffin | Oct 08, 2002 07:25am | #5

   With foam sprayed you don't need venting. That's why I like it best for cathedral ceilings. They can be tricky to vent.

   Was the reason you wanted 2x8 instead of 2x6 for insulation thickness?.

   Excellence is its own reward!

2. 
   Framer | Oct 07, 2002 05:25am | #3

   Fupcreek,

   I agree with Piffin, you only have 11' run on the rafter, plus whatever your overhang will be, you can use 2x6's  and 2x8's for the hip.

   Worst case if it's a low pitch you can use 2x8 and 2x10 for the hip, all with 16" oc.

   I've never stick framed a house with 2' oc befor unless we used trusses.

   You have to be carefull if you use 2x6's if you have a cathedral ceiling.

   I'll tell you why. Sometimes when we frame hip roofs we make Tray ceilings out of them and use the jack rafters and the hips for that ceiling. In New Jersey anything that is cathedral cannot be anything less then a 2x8 for insulation reasons.

   Hope this helps.

   Joe Carola