[lpranger467]

Months ago I posted up an idea I had for a 2nd floor addition. Because I have a stone house and we didnt frame interior to handle a 2nd floor I'm now instead looking at going out of the back with a sunroom-3 season addition room. I have a bump out on the back of my house about 11 feet across. Im gonna remove half the pergola seen in the pics so I can mirror this bump out for the room.

My issue is I have weird framing on the roofline. The roof has a drop down ledge on the right which is a consistent 6 inches deep, the left side however is sloped. I wanted to do a gable roof but wonder if a shed style roof would be easier as that I could run new rafters all the way to the roof and the different lips on either side shouldnt matter. But I do think a shed dormer wouldnt look as nice otherwise.

Looking for thoughts

 

[lpranger467]

From ground

 

[Nealtw]

From ground

So 11 ft would be against the house?
How wide is the bump out for the door?

 

[lpranger467]

Yes 11 feet wide and deep. The door bump out is actually only 9.5 feet so I would end up extending the walls 1.5 feet over to the right side.

If you can see in the one picture the bumped up angled part of roof doesnt even match the below bump out (roof area is maybe 7 feet and they put metal on the flat areas on the bottom on both sides.

My initial thought was to widen this area of the roof first so it would be as wide as the room, I would have to trace the angle on the left side and long cut it onto scab rafters. Then on the right I'd figure exact drop and just extend roof over. My issue with doing this is I think it would mandate a shed style roof then.

 

[Nealtw]

Yes 11 feet wide and deep. The door bump out is actually only 9.5 feet so I would end up extending the walls 1.5 feet over to the right side.

If you can see in the one picture the bumped up angled part of roof doesnt even match the below bump out (roof area is maybe 7 feet and they put metal on the flat areas on the bottom on both sides.

My initial thought was to widen this area of the roof first so it would be as wide as the room, I would have to trace the angle on the left side and long cut it onto scab rafters. Then on the right I'd figure exact drop and just extend roof over. My issue with doing this is I think it would mandate a shed style roof then.

You would make changes to the house roof which would allow either a shed or a gable roof.

 

[lpranger467]

Just to make sure I'm understanding, are you saying I would need to widen the bumped up area in order to connect the gable roof into it ? would you recommend this or should I just do shed roof

 

[Nealtw]

Just to make sure I'm understanding, are you saying I would need to widen the bumped up area in order to connect the gable roof into it ? would you recommend this or should I just do shed roof

I would do the same if I was doing a shed roof.

The one on the left I drew in a valley but it could go right to the peak.

 

[ron45]

Why not a flat roof addition.?

Then simply do nothing to the existing roof.

One example.

 

[lpranger467]

I had considered that (flat roof) but we can still get fairly heavy snow here and there (in Philly) not sure if it would hold up long term

 

[ron45]

I had considered that (flat roof) but we can still get fairly heavy snow here and there (in Philly) not sure if it would hold up long term

Does philly not have row homes and are they not 60 to 100 years old.?

https://www.google.com/search?sourc...pAhUqhHIEHRRNBfIQsAR6BAgJEAE&biw=1920&bih=937

 

[lpranger467]

We definitly have a point there. I do know these still have a slight slope and drain on a corner. Would I just slightly angle the rafters or cut a slope ? (my longest span will be about 11 feet).

I know I had originally said I was against a shed style roof but I may bite on this, I dont really want to re-roof half of my back roof

Does philly not have row homes and are they not 60 to 100 years old.?

https://www.google.com/search?sourc...pAhUqhHIEHRRNBfIQsAR6BAgJEAE&biw=1920&bih=937

 

[Nealtw]

We build solid surface decks here. 2x10s with 1/4" per foot slope. We would just build the far wall 3 3/4" lower and the side walls would have an angle.

With a bigger snow load you may have to go up to 2x12s or even LVLs , A lumber yard might help you figure that out.

 

[lpranger467]

Not sure if a rafter table would show this or not, but at 11 feet out if I used a 2 x 12 I'm be looking at roughly 8 inch on the load bearing wall. Do you think that would be adequate ?

We build solid surface decks here. 2x10s with 1/4" per foot slope. We would just build the far wall 3 3/4" lower and the side walls would have an angle.

With a bigger snow load you may have to go up to 2x12s or even LVLs , A lumber yard might help you figure that out.

 

[Nealtw]

Not sure if a rafter table would show this or not, but at 11 feet out if I used a 2 x 12 I'm be looking at roughly 8 inch on the load bearing wall. Do you think that would be adequate ?

No. you don't taper them. If you need a level ceiling you would sister them with level 2x6s.

 

[lpranger467]

Thanks Neal. Because I want an overhang (sides and backwall) I will probably have to frame the existing roof bumpout wider than 11ft I would imagine or should I keep it at 11 then just start overhang near the eaves ?

No. you don't taper them. If you need a level ceiling you would sister them with level 2x6s.

 

[Nealtw]

Thanks Neal. Because I want an overhang (sides and backwall) I will probably have to frame the existing roof bumpout wider than 11ft I would imagine or should I keep it at 11 then just start overhang near the eaves ?

You would make the roof 13 ft wide and you can make it bulky or you can do the over hang 2x4 or 2x6 by just cutting the back over hang of the rafters up to 2x4 or 2x6 and notching the the rafters over the wall for look out stays.

 

[Nealtw]

Thanks Neal. Because I want an overhang (sides and backwall) I will probably have to frame the existing roof bumpout wider than 11ft I would imagine or should I keep it at 11 then just start overhang near the eaves ?

6" might be better if you think about sheeting waste or if you are using the same plywood for roof and floor you could cut your floor plywood with the roof plywood in mind and still get 13 ft.

 

[lpranger467]

Thanks again