Replies

1. 
   skid1 | Oct 26, 2008 05:03pm | #1

   Yes, I would measure existing and layout/plan for new to match. You may have to open up some of the old soffit to measure it and see what to do. 

   If the roof pitch of new matches existing and wall heights of new match existing then all you have to do is construct new soffit to same dimension of existing and voila!

   If you want information about how to make different pitches and plate/wall heights match you will have to include that information in the question.

   I see that you are a new member, and that this is your first post so I am making a feeble attempt at polite, but vague questions usually get vague answers. The more detailed your description of the problem you are trying to solve the more help we can be.

   Frequently a detailed written description of the problem will itself solve the problem in that when you read it the answer becomes obvious. Remember there is no such thing as a stupid question, but if I wrote a question that answered itself I would post it with the additional question asking for different approaches/techniques.

1. 
   philzee | Oct 28, 2008 02:45pm | #6

   Thanks, the new roof does have the same pitch as the existing roof, ido plan to get to the soffits today so I'll see how it goes. Thanks for the posting advice

2. 
   Framer | Oct 26, 2008 10:34pm | #2

   i'm adding a 20x20 addition to a ranch home. one end is flush with the house and the other side will need to have the soffits line up. The architect has me sistering in 2x4's for the rafter tails. Any advice on the best way to align the soffit

   You have to be more specific than that.

   1) Do you have the same plate height?

   2) Is the new roof a continuation of the existing roof with the top of the new roof planing in with the existing roof and the same pitch?

   3) If yes to #2, are the new rafters the same size?

   4) Is the addition roof not planing in with the existing roof and has a different pitch/same pitch?

   5) If yes to #5, are the plate heights the same and rafters the same size as the existing?

    

   Joe Carola
1. 
   brownbagg | Oct 26, 2008 11:28pm | #3

   I see so many houses screwed up because of soffit, different in height and size. Maybe they need to build the soffit first and go up from there.

1. 
   Framer | Oct 27, 2008 12:11am | #5

   I see so many houses screwed up because of soffit, different in height and size. Maybe they need to build the soffit first and go up from there.

   There are many scenarios here. The fascia lines and soffit lines can line up perfect, but the overhng can be different. I can make any fascia line and soffit match without doing the overhang first. He just has to answer some of the questions.

   He can have the top of the roof lines plane in with the same pitch but different size rafters dropping the plate height. He can have a steeper pitch with the fascia and soffit lines perfect, but different overhang.Joe Carola

2. 
   philzee | Oct 28, 2008 02:47pm | #7

   Thanks Joe,

   The new roof is pependicular to the existing, wall heights are the same. New roof rafters are 2x8's. Existing are 2x4 trusses

   Phil Candando

1. 
   Bing187 | Oct 28, 2008 05:55pm | #8

             You need to find the "height at plate " dimension on the existing roof. This is the measurement in a vertical line from the plate to the top of the truss at the outside of the plate. If you can match that without taking to large a birds mouth out of the 2x8, then you're golden; just make the height the same at the plate line, and the height of fascia and width of soffit will match.Don't forget to figure for the 1/2" ply if that's where your bird's mouth will catch the wall on the new part. If the birds mout ends up too big, your options are to have a wider soffit on the new part to keep fascia height same, or drop wall height, ( probly not an option).

           Out of curiosity, why 2x8 on the new part? I stick build most of my stuff, but in this case, you could get the trusses made to match HAP exactly....Seems it would save ya some trouble.

           ( Hope I'm not steppin on your toes answerin a post to you, Joe, but it's pourin and I'm bored  :)

   Bing

1. 
   philzee | Oct 28, 2008 06:17pm | #9

   Thanks Bing,

   The reason why we could not use trusses is this is a cathedral ceiling with only a 4/12 pitch, the architect chose 2x8 and I am going to sister on the rafter tails, it probably won't be too difficult based on the responses I've gotten. Thanks for your help

   Phil

1. 
   Framer | Oct 28, 2008 07:34pm | #10

   I am going to sister on the rafter tails,

   Why would you sister on the rafter tails and not cut them with the rafter?

   Is the top of the 2x8's supposed to be flush with the top of the trusses planing into with them for a continuos roof?

   The reason why we could not use trusses is this is a cathedral ceiling with only a 4/12 pitch,

   What size ridge beam does the Architect have spec'd, and how does he have it supported where it hits the trusses?

    Joe Carola

2. 
   Bing187 | Oct 28, 2008 08:55pm | #11

          I don't think the structural ridge would bear on any part of the old roof, as the op previously said the new roof runs perpendicular to old, with one wall flush, and other needing sof to line up. I assume the old roof would be a continuation/layover onto the new roof.

          I can see with the cathedral why you wouldn't go truss; if the roof is a 4/12 by the time you scissor with a truss, you wouldn't have much of a cathedral. However, as Joe pointed out, two issues remain. One; do you have a ridge sized by an engineer to bear on the peak ends, since you won't have anything tying the walls together, ( although what I'm picturing would be the rafters sitting on the wall of the existing peak end of the house on 1 side with the exception of a small portion), 2; there shouldn't be a need to sister anything. You would come out the width of your fascia on the new rafter, make your vertical cut to line up, and cut off whatever hangs down at the horizontal soffit point.

   Good luck

   Bing

3. 
   philzee | Oct 30, 2008 01:22am | #16

    

   the ridge is 5 1/2 x 16 it is supported by a 6x6 lam post at each end. The ridge is installed and most of the roof is framed. The reason the architect specified sistering the rafter tails was to make it easier to line up the soffits. I'm going to be doing the soffits this weekend and I'll let you know how it goes.

   Thanks for all of your help

   Phil

4. 
   Framer | Oct 28, 2008 09:23pm | #12

   Is the roof something like this?

    

    Joe Carola

   
5. 
   philzee | Oct 30, 2008 01:16am | #15

   Yes Joe the roof is exactly like the one you drew

2. 
   Kyle | Oct 29, 2008 02:24am | #13

   You forgot one part of the equation. If the H.A.P. is the same and the pitch and the overhang are the same then they will line up. If not then I usually just referance the drop in the overhang which I usually just measure from the top of the wall. Then for example if you have a 12/12 pitch with a 1' overhang you would have a 1' drop, so if you made a 6/12 with a 2' overhand you will still have a 1' drop and the fascia will line up. By adjusting the width of the overhang you can line up the fascia to factor out the h.a.p. which comes in handy if you are tying a stick roof with a truss roof.

1. 
   Bing187 | Oct 29, 2008 06:15pm | #14

         Actually, in my first post, I offered that as an option; wider overhang.. I try to avoid that if I can tho, as it makes the transition from original house to addition more apparent...We're on the same page.

   Bing

3. 
   CapnMac | Oct 26, 2008 11:45pm | #4

   Any advice on the best way to align the soffit

   Yes.

   First best way to not spend extra time and effort is to not try in the first place.

   As both Joe & BB point our, there are more ways for old and new to not match than to match.  Far better to design a simple detail that makes a simple break between the two.

   This is no different than the way all of the rest of the finish carpentry is handled in our houses--why we expect differently for soffits, fascias, and the like continues to boggle me.

   Given that this is already "designed" and by inference already under construction, I'd plan on making the soffit change 50/50.  That is, rip half the change out of the old and half into the new.  That could be a foot, could be two, might be four feet either way, depending on the way old and new are detailed.  Might be that you can get into the old work and "strap" back into the new, and that will make a nice transition.

   Do note that, even if there is an easy way to make a smooth transition from old to new, some transition may have to be made, somewhere.  In that case, moving the changes away from each other helps break the impact having all of the changes in one spot can have.

   Occupational hazard of my occupation not being around (sorry Bubba)