Sometimes I get a little perplexed at things I see. I know it’s not the way it’s supposed to be constructed. Problem I sometimes face is will this modification of the rafters to change the pitch work as constructed?
They scabbed 2x4’s to the side of the existing rafters to change the slope of the roof…which also changed the ridgeline.
I could defer this to a qualified contractor, however a qualified contractor (so they said) made the modifications.
Hi Kevin,
that looks very ammatuerish at best, if in doubt I would refer the buyer to a structural engineer. The support structure under the rafters looks very light to me.
Regards
Gerry
The only issue I see, assuming rafter ties are installed, is the sheathing nailing schedule. A typical nailing schedule for fastening roof sheathing would be 6 inches around each sheet perimeter and 12" in the field.
Since the rafters in the near side of the picture have had furring strips added to the top of them, sheathing is nailed to the furring strips rather than to rafters. The nailing schedule fastening the furring strips to the rafters can’t be checked at this point, so there’s no way of determining whether this change is sufficient to withstand uplift. Technically, it should be engineered.
That’s what I’d state in the report.
Realistically, it’s probably fine if a nail gun has been used. People love to shoot those guns and they’ll put nails everywhere.
On the original construction, the bottom edge of the roof rafters underhang the ridge.
It’s not a professinal install any way you look at it!
How much overlap is there between the original rafter and the sistered member, and what is the nailing schedule? As long as they shot enough nails into it, I would not have a problem with it. Kenton is right though. Technically it ought to be engineered.
I thought it was a furring strip nailed on top of the rafter, rather than another rafter sistered along side. Hard to tell from the photo.
Sistered would be better since nail failure would be a shear failure rather than straight pull like furring strips.
Looks like the ridge was offset from the original framing for some reason. Maybe someone wanted it to line up with something else, and didn’t care that two different roof slopes would result.
The front slope and back slope were at different angles…tha’ts the way the house was designed…I’m guessing that they when they put an addition on it had a different slope roof. So when they reroofed the exising, they changed the slope to match the addition…it was just a poor way of going about it.
Those are 2x4’s scabbed onto the 2x6…with a 2" reveal, it leaves only a 1 1/2 " of nailing area.
I could be wrong, but it looks to me the 2x4’s are scabbed to the top of the rafters which carry the load…not scabbed to the sides, if that is what I’m seeing, I wouldn’t have a problem with it. Beefing up the rafter attachment to the ridge would certainly be in everyones favor though.
Are they on the top?..or sides?
yes…you are wrong.
I know for a fact.
Is this what your taliking about Kevin?
Yes…those 2x4’s are scabbed to the sides of the existing rafters to change the roof deck slope.
Looks like the top to me…sorry.
For a minute after you saying they were scabbed to the sides…I was wondering if you meant these.
Yes, if those 2x4’s were scabbed to the top, I would have less worries.
I understand now Kevin, and yes i would be concerned also…good call.
I didn’t get the full picture in my mind when you had the light pointed at the top where my first picture points arrows.
Hope all is well up there, and business is picking up in the spring.
The load on each rafter is tiny, and it wouldn’t take many nails to resist the load. I don’t see it as a serious concern. Same witn the attachment of rafters to ridge; the ridge is just a nailer, basically…it carries no load. Now that we know the reason for it, it doesn’t seem to be a problem.
Tiny??? Doesn’t it snow in Wisconsin? I bet an engineer would want to see a .131 16D nail (the ones typically used in nail guns) at least 8" on center to resist the live and dead loads in this roof system.
problem with nail guns is that alot of installers don’t adjust the air pressure so the nails get overdriven, esp on sheathing, and more esp on 7/16" osb sidewall sheathing. if the installers are careful enough to monitor nail depth, then they are mindful enough of the proper nail schedule.
regarding the roof, it looks like someone probably didn’t know how to frame that roof correctly and made a boo-boo adjustment. defer to a structural engineer.