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Old 12-22-2008, 05:22 PM   #16
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joist span/beam spans


A 4/12 roof pitch will drop 32" over 8' so you might have 8' headroom at current soffit but it will be down to 5 and 1/2 feet at the outside edge. A 3/12 pitch will drop 24" and that's getting pretty shallow for shingles.

Are you thinking you can't bolt a ledger to your foundation? Looks like brick veneer and its true that you generally shouldn't use brick veneer for bearing a deck but since the height would be minimal your local authorities might allow it. If not you could put in piers near the wall and make it freestanding.

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Old 12-22-2008, 06:01 PM   #17
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A 4/12 roof pitch will drop 32" over 8' so you might have 8' headroom at current soffit but it will be down to 5 and 1/2 feet at the outside edge. A 3/12 pitch will drop 24" and that's getting pretty shallow for shingles.

Are you thinking you can't bolt a ledger to your foundation? Looks like brick veneer and its true that you generally shouldn't use brick veneer for bearing a deck but since the height would be minimal your local authorities might allow it. If not you could put in piers near the wall and make it freestanding.
I am not sure I follow you. The peak of my current roof is approx. 13.5 feet above the top of my deck surface, and 5.5' above my top wall plate. If I do a gable roof spanning 32 feet, I can do a 4/12 pitch. 16 feet on the left dropping 5.5' and 16 feet on the right dropping 5.5 feet.

From what I understand a 4/12 pitch is the minimum for architectural shingles. I hope I'm ok. If I have to drop my porch overhead to 7.5 feet I will.
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Old 12-23-2008, 10:36 AM   #18
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I am not sure I follow you. The peak of my current roof is approx. 13.5 feet above the top of my deck surface, and 5.5' above my top wall plate. If I do a gable roof spanning 32 feet, I can do a 4/12 pitch. 16 feet on the left dropping 5.5' and 16 feet on the right dropping 5.5 feet.

From what I understand a 4/12 pitch is the minimum for architectural shingles. I hope I'm ok. If I have to drop my porch overhead to 7.5 feet I will.
I was assuming you would continue the current roof lines and not rebuild the roof over the existing house. So your roof would start at the height it currently is over the double plate and then decrease 1 foot for every 3 foot from the wall.

I suppose you could put a gable end roof over it but it can't dive into the garage roof. That would leave you a flat valley between the current garage roof and the new porch roof which would leak. You could put a big gable over both the porch and garage but would that look ok? Is that the 32' you are describing? It would cost a lot more than dropping the deck 32".

Just about everything I've read says 4/12 or steeper for shingles. I've seen occasional uses of 3/12 if absolutely necessary and if snow isn't a factor but 4/12 is probably a better minimum.
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Old 12-23-2008, 01:14 PM   #19
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One thing that I would like to say is that using a ledger board is not a good idea! Two rows of beams, supported by piers, and keeping the deck removed from the building would be my choice! I just finished helping my neighbor put in new piers and beams. Rot had penetrated from behind the ledger into the rim joist and caused extensive damage!
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Old 12-23-2008, 03:08 PM   #20
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I was assuming you would continue the current roof lines and not rebuild the roof over the existing house. So your roof would start at the height it currently is over the double plate and then decrease 1 foot for every 3 foot from the wall.

I suppose you could put a gable end roof over it but it can't dive into the garage roof. That would leave you a flat valley between the current garage roof and the new porch roof which would leak. You could put a big gable over both the porch and garage but would that look ok? Is that the 32' you are describing? It would cost a lot more than dropping the deck 32".

Just about everything I've read says 4/12 or steeper for shingles. I've seen occasional uses of 3/12 if absolutely necessary and if snow isn't a factor but 4/12 is probably a better minimum.
Thanks jogr, you have educated me a lot and given me more thought about this project. I do not have the option of dropping the porch. For one, it just won't look right. The top of the windows would be hidden behind the top of the roof. I'm not interested in doing that.

Here is my other option. This is NOT my house, but one I found online that is built very similar. I could leave a gap in the opening of the entryway. The entry door is already set back 4 feet from the edge of the current roof.



I could then build a shade arbor over the top between the 2 gable ends of the porch and garage. Maybe there are other options too? (I am 100% against dropping the porch more than 5 inches becuase of the tops of the windows. )I know this maybe isn't ideal...I guess I don't have a choice other than to build a deck on the front of the house with no roof or skip the arbor and leave the house like the one pictured. I am not sparing expenses. I have used flashing and waterproofing membrane behind the ledger, flashing on top of the ledger and caulking all around. I also purchased $180 worth of BigFoot Footings, so I am interested in doing this the right way, but I guess after 4 contractors gave me bids and never mentioned the intersection of 2 gable roofs, I assumed I was ok. I will be sure to ask the guy about it.

Last edited by my5sons; 12-23-2008 at 03:59 PM.
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Old 12-23-2008, 03:22 PM   #21
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By the way, I contacted GAF shingles and they said that 2/12 is the minimum slope when using their shingles. If I went with a shed style roof, I could probably make this work. I just have to overlap the underlayment a minimum of 19".
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Old 12-23-2008, 03:54 PM   #22
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Here is another photo showing the idea of what I am talking about: (notice the opening between roofs ends.)

http://www.homebuyershandbook.org/ra...le-homejpg.JPG
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Old 12-23-2008, 04:19 PM   #23
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The opening between the gables is a good idea. The contractors might have been planning to put a very shallow sloped "triangle" between the gables (I forget the roofing term at the moment) but it would have very little slope and could easily lead to water issues.
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Old 12-23-2008, 04:36 PM   #24
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Personally, I think that extending the gable is the only option. Anything else would look like hell! Maybe a flat roof between the gables for the entrance, covered with a rubber membrane would be OK!

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