Changing a dormer roof from shed roof to gable
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Changing a dormer roof from shed roof to gable
I look at problems as opportunities, so with the discovery that the rafters in my dormer are junk, I started thinking 'A gable roof over this dormer would really look better, while I'm at it'
The shed roof, according to the rafter tabels and the species of wood available, would take 2x10 rafters on 16" spacing. (clearly, 2x4 on 24" spacing is inadequate, I don't care how great the species of wood it was built with!!)
Rather than that, it's a 6' wide dormer, the framing would be alot easier to handle for the roof with 2x6 rafters, so I'm leaning towards that. The peak of the dormer wouldn't be at the peak of the rest of the roof. So I'm wondering if I could get some guidance as far as what I need to do to properly support the dormer roof within the main part of the roof. (which is framed with 2x4 rafters on 24" centers, supported mid-span by the knee wall, and covered with 1x6 sheathing with OSB over it.)
The shed roof, according to the rafter tabels and the species of wood available, would take 2x10 rafters on 16" spacing. (clearly, 2x4 on 24" spacing is inadequate, I don't care how great the species of wood it was built with!!)
Rather than that, it's a 6' wide dormer, the framing would be alot easier to handle for the roof with 2x6 rafters, so I'm leaning towards that. The peak of the dormer wouldn't be at the peak of the rest of the roof. So I'm wondering if I could get some guidance as far as what I need to do to properly support the dormer roof within the main part of the roof. (which is framed with 2x4 rafters on 24" centers, supported mid-span by the knee wall, and covered with 1x6 sheathing with OSB over it.)
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Okay let me be a little more specific here about what I think I have figured out and what I'm not so sure about.
Rafters and sidewalls on the gable dormer make sense, that's simple enough, and the ridge beam is straight forward. The end wall will use the existing end wall, which I believe may be baloon framed, but either way that's going to be close to all I'm reusing besides siding. And I get that I will need to put in valey framing and a double header.
Here's what I'm not so sure about: I'm thinking it would be idea to triple the common rafters. Like I said, the rafters are 2x4 on 24" spacing, I'd like to go up in size, but the only way I can do that is to keep the top flush and the let the extra width stick out below. This is obviously no issue in the attic, and I don't see any problem aestheticly with the part where it will stick into the room, where my question is if this is an issue where it attaches to the wall framing since typically the support would be at the bottom of the board notched to 1/3 of the thickness, but in this case the support would be higher up.
Rafters and sidewalls on the gable dormer make sense, that's simple enough, and the ridge beam is straight forward. The end wall will use the existing end wall, which I believe may be baloon framed, but either way that's going to be close to all I'm reusing besides siding. And I get that I will need to put in valey framing and a double header.
Here's what I'm not so sure about: I'm thinking it would be idea to triple the common rafters. Like I said, the rafters are 2x4 on 24" spacing, I'd like to go up in size, but the only way I can do that is to keep the top flush and the let the extra width stick out below. This is obviously no issue in the attic, and I don't see any problem aestheticly with the part where it will stick into the room, where my question is if this is an issue where it attaches to the wall framing since typically the support would be at the bottom of the board notched to 1/3 of the thickness, but in this case the support would be higher up.