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I am doing an addition on my house and the existing house isbrick with an 5.5 brick ledge. My addition will have siding, on the same plane as the brick, with a trim board where the two meet. Will it be possible to match the existing rafters with the new rafters and still have both roof lines on the same plane. The way i see it since the new walls will be 5.5 inches further to the outside, it will raise the rafter up above the existing roof line. Can i just make the birdsmouth deeper on the new rafters to make them plane out with the old roof line. They are pouring concrete tommorow and I need to now where to set my anchor bolts. My foreman came out and said i need to line the new stud wall with the old stud wall and be done with it. But then I am stuck with a detail where the old brick wall flows into the new siding wall. I hope I have been clearly understood Thanks for any replies.
cutawooda35
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cutawooda35, refigure your roof pitch using the same total rise as the existing structure and the run (half the total span) of the new addition. Do the math and it will come out ok. Your new rafters may be a 5.3 to 12 or something odd like that.
I am guessing that this is an addition on the end of the house. Which ever way you choose is correct. Siding flush with the brick or stepped back so the interior walls line up. I would suggest you work out that detail before you pour your foundation wall.
Go to Joe Fusco's web site for a good primer on roof framing. He makes it easy to understand.
*I'm also guessing that you are framing an addition onto the end of a gable roof. So, the brick forces your rafters out 5 1/2", and if you lay them on at that length,the roof will be out of plane. Right?Well, you could build the walls a little shorter or cut the bird's mouths a little deeper (depending on how much meat is left in the wood). Adjust your rafter tails to keep your soffit and fascia in line.Shouldn't be too tough. If it has to be out of plane for any reason, I'd change the pitch completely, and drop or raise this section, you pick. Make it substantially different.If it were me, and I had to set anchor bolts, I'd set them in line with the other walls. If that needs to change, you can always saw them off and drill in some new ones. I don't sweat anchor bolts too much. But, I don't live in hurricane country either, maybe it matters more where you live.MD
*I'd align the new walls with the old. You don't say what the pitch is or what you're planning on using for rafter material, or what the overhang is, so I can't say if you'll be able to deepen the birdsmouth. But, you can always frame the addition walls 2 or 3 inches lower, which will also solve your problem. A 5.5" jog would look pretty odd.
*The reason for not wanting to align the old and new stud wall is because I will be stuck with an unattractive corner detail where the brick sticks out further than the siding. Also the forms are already in (slab) and if I line up the stud walls I will be stuck with a 5.5" exposed brick ledge that will catch water. Roof is a 6 pitch. 2x6 raftersthanks for the help
*Well, what I meant was to line up the outside of the wall with the outside of the brick, allowing for whatever sheathing and siding you're planning to use.That low pitch and small rafter won't help the birdsmouth situation much. Hard to drop the cut on a 2x6 unless you have a lot more pitch.So how about framing those walls a little shorter. You can use your overhang as a "template" maybe to guess basically how much shorter and how to cut the bird's mouth.
*Ok...I am losing faith in my idea. I didnt really think that moving the wall out 5.5 " would affect the birdsmouth that much..I guess I was wrong. for the life of me I cannot figure out how high to cut the walls if I shorten them. Without the ridge up how do u know. I guess i might have to forget the idea of lining up the roofs. I will have a valley now but i DO NOT want the exposed 5.5" on the slab. I can see it leaking easily.
*Um, can you try working this out on paper? Have you made a scaled drawing of what you're trying to build? If not with a t-square, then at least on graph paper. One inch=one foot scale is easy to work out with a standard ruler, and big enough to draw out wall thicknesses, studs, brick, etc..
*Another option would be to truss the new roof. The truss manufacture would then raise or lower the bottom cord of the truss to match your existing roof plane. Most of them are pretty good at matching up to existing roofs.
*I'd get on a ladder and look at the wall you have now. then, project your view out to where the brick wall ends. it should be fairly easy to guess how much to lower the walls. Then, set your ridge, cut two 2x6's (one for each side) with the proper ridge cut and leave the tails run long; maybe you can rig up something to hold the rafters at a certain height with clamps. If the roof plane is too high, then lower the clamp a bit until it lines up. Now you've got your ridge temporarily supported, your rafters in the right plane. Take a wall stud and plumb it up to the rafter in line with your other wall, scribe the bottom of the rafter onto the stud. Now decide how much of it to make into the bird's mouth, draw a level line, subtract 4 1/2 inches (for double top plate and single sill plate) and you've got your stud height and your birds mouth cuts. All that's left is getting your fascia cuts.Not so hard. Just start cutting and trying to fit. It's only a couple 2x6's, what have you got to lose?
*I also meant to line up the new wall with the brick. If you're using 2x6 rafters, and move the wall out 5.5", your birdsmouth with be 3" (nearly) deeper. Won't have much of a 2x6 rafter left. Think about it, 6/12 pitch means 3" rise in 6" (close enough to 5.5"). Lower your walls 3", and keep them aligned with the brick.
*By the way, this is assuming your existing rafters are 2x6 as well....
*If you move your wall out exactly 5 1/2" you drop your wall 2 3/4". This will allow the rafters to line up with standard birdmouth.That doesn't allow anything for sheathing and siding.So, whatever you are allowing for sheathing and siding thickness you have to back up the wall. For each 1/4 " you back up, increase the height of your stud wall by 1/8".On the inside of the addition you will either have a slightly lower ceiling where it meets the wall or you can thicken the framing to the interior to match the rest of your ceiling heights.
*Yep. And it's rough framing. You're not doing a staircase, it's just a roof. If you're not happy with the height of the new plane height, you may be able to adjust it with different size ply for sheathing to get closer to the old roof. If you miss by a little bit, it won't matter much.
*Thanks for the help. I guess since I am going to use i/2 osb for sheathing I will need my wall to be 2 1/2 inches lower. I will be using lap siding that projects 1/2" but I want it to overlap the slab, so it will be excluded in the formula. Speaking of formulas..how did you arrive at the 2 3/4"thanks for the [email protected]
*I put my brain into gear, sharpened three pencils, got out a stack of paper and.................... cheated.
*Cutawood,YOu have lots of choices.You might move the wall out, then double frame inside to make the inside wall flush.You could keep the inside wall flush, then furr out the outside wall a little bit and run it all the way down to the brick ledge.You might cantilever the wall out and brick up to the bottom of the wall, thus eliminating the brickledge.You might adjust your heel 2.75" (6/12 x 5.5) if there is enough material left in the birdsmouth (probably not). YOu could lower the wall 2.75" if that does't affect your ceiling situation.Lots of possibilities....lots of unanswered questions.blue
*If you follow Ralph's previous posts, you'll see that on a 6/12 roof there is an even progression of losing or gaining 1/2" of height for every 1" it moves horizontally. So, if you move it out 5 1/2", it will lower the wall by 2 3/4".
*The slab is wrong....Dropping the wall is corrective wrong number 2...setting up a lower ceiling height solution will be wrong correction number 3....and so on...till yaa pack up and drive off for an 18 pack of your favorite medicine.I would cut back the slab and build it as the boss said. The brick to wood detail is a snap compared to all this other correctivity.near the stream,aj
*Why can't you just draw a full scale section on a piece of plywood. Draw it first the way the existing rafters hit the existing wall. When you draw out what you are proposing to do, you'll see right away what changes you need to make in wall height or birdsmouth dimension to make the roofs line up. It'll also tell you how you need to step in your foundation.Mike Patterson
*Thanks for everyones help! I decided it would just be easier if I tie my new stud wall in with the old stud wall that is behind the brick. I know that I will have 5.5" of slab showing but I will just flash it and seal it really well. The thought of all the trouble of cutting all the studs compared to justmaking a return on the brick wall to the siding wall was too much for me to bear. I could still change my mind and cut the anchors and re-install thewm out to the edge of the slab..but the concrete crew came and poured so I opted,(for now) to install them in-line with the existing stud wall. Now my worry is rain getting on the 5.5" exposed salb and creeping under my sill. I t will all work out in the end.'thanks againCutawooda35.
*That's what water tables were designed for.When you get around to sheathing and flashing you could make a sloped water table at that point.See Mike Smith's thread in the Gallery. Use some Trex like he did and you'll have a nice little accent.
*Could you elaborate please. I was out @ 11:30 last nite after the concrete guys left and scraped out a 1/2" deeep ledge so water would not get under the stud wall. In hindsight I should have had them install a brick ledge just like the existing wall. I was in such a state of indecision though,.... Is you accent you speak of like a 2x6 laid in the ledge. Now I need to smooth out or cover my handiwork last nite.Thanks Cutawooda35
*Check out Mike Smith's posts in the Gallery under "OJT". His actual water table pictures are better than my drawings.
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I am doing an addition on my house and the existing house isbrick with an 5.5 brick ledge. My addition will have siding, on the same plane as the brick, with a trim board where the two meet. Will it be possible to match the existing rafters with the new rafters and still have both roof lines on the same plane. The way i see it since the new walls will be 5.5 inches further to the outside, it will raise the rafter up above the existing roof line. Can i just make the birdsmouth deeper on the new rafters to make them plane out with the old roof line. They are pouring concrete tommorow and I need to now where to set my anchor bolts. My foreman came out and said i need to line the new stud wall with the old stud wall and be done with it. But then I am stuck with a detail where the old brick wall flows into the new siding wall. I hope I have been clearly understood Thanks for any replies.
cutawooda35