It's me again- sheathing questions and more..

[DEBL]

Hello Everyone,

I have what I hope are several easy questions about my roof.
We are preparing to install the sheathing and I'm not sure about a few things.
First, my rafter overhangs are not even on both sides. I will have a finished overhang of aprox. 10-1/2" on one side and 11-1/2" on the other. The rafters themselves are all in pretty much a straight line. (I don't think it would be worth my taking a chance to try cut them perfectly, because I can't cut straight anyway!) At least now the ends are all cut straight by the supplier! Will these uneven overhangs be a problem?

My next question is about where to stop the sheathing on the edge of the roof. Do I stop at the end of the rafters on the eave side and just before my fascia board on the gable over hangs? In other words do I stop my sheathing just before the fascia board that is going to be covered with aluminum or should I overlap the fascia board some?
Also, should I install ridge vent, if I'm going to have soffit vent? (Just a reminder this is a pole barn)
Hope you can help. ( I know you can :D )
Thanks~

[Dragon]

I say yes to the ridge vent. It will help keep the barn cooler.

As to whether or not you need to cut your rafter tails, well, I always chalk lined and cut mine. The difference might be noticeable on yours, and it might not.

[DEBL]

Hi Dragon,
Thanks, what about the sheathing?

[Dragon]

What pitch is your roof?

On steeper pitches I will actually let the decking hang out past the fascia board a bit so that the roof edge can be installed correctly, especially if it is Style D. Most people do not do this and have to smash theirs flat against the fascia so that it can be attached. This tends to make it rise over time which makes your shingles have a ski-jump effect at the bottom edge of the roof.

But your fascia should plane with your rafters and the decking should set on top of it.

[Tom R]

To me, that 1" is a lot. If you don't feel comfortable 'cutting' the rafters, simply 'sister' cleats to them, giving you 11 1/2" all the way.

[Dragon]

Ah, I know whats up. These are trusses. They were placed tight to one wall instead of being spaced with 1/2" hanging over on each side. Truss companys will often do that to allow for sheathing on the wall, which is often in place before the trusses are set.

DEBL, you can do as TomR suggests, but it will make one fascia board slightly higher than the one on the other side. Decide which evil is lessor for you and go with it. The only way to really fix it properly is to move the trusses 1/2 ".

[Tom R]

Good point, - - yeah, either move the trusses or 'compromise', - - meaning use cleats to make up 1/2" of that 1" difference.

[mjpliv]

Using cleats will extend the tails of the truss but it will also lower the fascia. Its a matter of choice - different heights or different overhangs.

Definately go with the ridge vent. Most offer 18" of free airspace per lineal foot. It not only helps to keep things cool but it helps to keep things dry. The more air moving around your attic space the better.

Dragon makes a good point about sheathing overhangs. There are no cut-and-dried rules about installing your sheathing. It depends on your final finish and roof pitch.