Results 1 to 39 of 39
  1. #1
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Deflection in roof

    House built in 2005. I just noticed this slight deflection only on on the front side of the roof in the middle. Any suggestions?

    Thank you!

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Crawl Space Creeper

  2. #2
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Just curious ... is that a current photo with the snowman holding the Christmas Tree?

    Regarding the deflection, are you referring to that small dark line near the bottom at the center?

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  3. #3
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    Just curious ... is that a current photo with the snowman holding the Christmas Tree?

    Regarding the deflection, are you referring to that small dark line near the bottom at the center?
    Haha! No, it was from December of this past year.

    No, it's the spot at the ridge right above that area where it looks to be sagging right at the top. I know it's very slight but it's easier to see in person.


  4. #4
    Join Date
    Feb 2008
    Location
    Caledon, Ontario
    Posts
    4,982

    Default Re: Deflection in roof

    Could be broken rafter, 3/8 plywood decking.

    Have you checked in the attic?


  5. #5
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    No, it's a vaulted ceiling. How would I do that?

    i had the house inspected. I just purchased it in September and moved in November and the inspector never mentioned it. I only noticed it last week and then found this picture that I took in December.

    is this a hard thing to repair?


  6. #6
    Join Date
    Feb 2008
    Location
    Caledon, Ontario
    Posts
    4,982

    Default Re: Deflection in roof

    Since its a cathedral you cannot access it. You could walk the section of the roof and feel if it is springy.

    If it feels solid its likely okay. If not the area would have to be accessed from the outside for repairs if required.


  7. #7
    Join Date
    Mar 2008
    Location
    Charlotte NC
    Posts
    2,304

    Default Re: Deflection in roof

    Quote Originally Posted by Raymond Wand View Post
    Since its a cathedral you cannot access it. You could walk the section of the roof and feel if it is springy.

    If it feels solid its likely okay. If not the area would have to be accessed from the outside for repairs if required.
    Most vaulted ceilings have attic area between the ceiling and the roof. Look in the attic but be careful, most do not have walk boards.

    (Sorry Ramond, I thought I quoted her post)

    The beatings will continue until morale has improved. mgt.

  8. #8
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    I doubt it really is anything as it is all too common for trusses to be installed such that they do not line up properly.

    It is not uncommon for trusses to "not exactly match" in height, span, slope, etc., especially scissors trusses as you would have for a vaulted ceiling.

    There are four basic ways to install trusses: 1) swing the trusses into position and, using a string line along the eaves, usually the front eave which faces the street, align the trusses so the eave truss tails match, then strap/clip down; 2) swing the trusses into position and, using a string line along the ridge, align the trusses so the ridge matches, then strap/clip down; 3) swing the trusses into position and visually align one face of the trusses, usually the front face which faces the street, then strap/clip down; 4) swing the trusses into place and strap/clip them down.

    If the installers did it as in 4), it is hit or miss that anything will line up - quite often no one notices anyway.

    If the installers did it as in 3), then the shingled face of the roof may be in or close to in plane, the eaves or ridge may not line up - most often no one notices because the roof looks in plane.

    If the installers did it as in 2), the ridge will line up and there will not be any dips (unless there is a dip in the sheathing) and the roof looks good along the ridge by may not match along the eaves.

    If the installers did it as in 1), the eaves will match up but the ridge may not and there may be a an apparent dip in the ridge (but the dip may not really be there as the peak of one truss may simply be behind or in front of the other truss peaks and (from standing on the roof) the ridge may simply bend side to side.

    Installers who are proud of their work may do 1) and 2) so that the front eave looks even and the ridge looks even, and any misalignment will be on the back where fewer people see it. Some will even shim the trusses up to match front-to-back alignment and also match height alignment trying to make the roof look as good as possible based on the trusses they are working with (few do this as there is too much competition in building construction and the bottom dollar is what usually wins out over quality construction.

    While there may be a problem with the roof sheathing or trusses ... I would not raise that flag unless I knew or was sure that there could be ... because it is usually just in the setting of the trusses.

    Unless it is quite pronounced, your inspector may not have been concerned about it - but you said "I know it's very slight but it's easier to see in person.", which causes me to think that it was insignificant enough that your inspector thought it was nothing to be concerned with - and probably 99%+ of the time it is construction appearance, nothing to be concerned with.

    You could call your inspector and ask what they think of it, that would be a good first step.

    Making any corrections, changes, or even a real good diagnosis may require going down into the roof from the top down. That means removing some shingles, some roof decking, and taking a look ... the problem is that if nothing is found you will have a repaired area on the front of the roof (the shingles pattern will shown even more than it does now).

    However, it depends on the slope of the roof outside versus the slope of the ceiling inside for this next thing: if your roof is like my roof, the inside ceiling peak is at 14 feet, yet I can stand up almost straight and walk across above it in the attic in the trusses, or it could be that there is no space to even be able to see much at all from inside the attic, in which case you would be back to going in from outside just to check it.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  9. #9
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Could this be the sheathing also?

    I will try to look up there with a flashlight. There's an access in my bedroom closet where possibly I can see that far.

    Should this have been something my home inspector should have noticed and addressed?

    Is this something I can leave until I have to get the shingles replaced down the road?


  10. #10
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Thank you for all the helpful information. I did email my original inspector so hopefully he responds.

    Is something that can be fixed when the shingles are eventually replaced if trusses are uneven?


  11. #11
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    Could this be the sheathing also?
    To be or not to be that is the question ... the answer is: possibly and possibly not.

    Should this have been something my home inspector should have noticed and addressed?
    Your inspector may have and the way they addressed it may have been "I don't see anything there which raises a red flag." and that was the end of it. Inspectors have to make those decisions on almost everything they inspect, to bring each and everyone of those things to your attention would probably scare the bejesus out of you and you may not end up buying anything ... that would not accomplish anything positive for you, would it?

    Is this something I can leave until I have to get the shingles replaced down the road?
    Depends ... (not the kind old people wear either ) ... The house is almost 10 years old and there is no apparent problems from it that you found, you only found that accidentally while looking at it. Depends on what it is, it may actually not be anything. We cannot tell from here.

    Quote Originally Posted by Catherine Newberry View Post
    Thank you for all the helpful information. I did email my original inspector so hopefully he responds.

    Is something that can be fixed when the shingles are eventually replaced if trusses are uneven?
    It may not even require "fixing" as there may be nothing "wrong" with it. If it is the truss alignment then it is almost surely cosmetic and the effort (and cost) to make it look better would probably far exceed what *I* would want to spend on it just to make it look better. But that could just be me.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  12. #12
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Okay,it looks like I can access the rafters. I only looked from the attic door because I wasn't sure if I can walk up there. It looks like there is a lightbulb on a cord hanging up there and a little platform. Is this normal? Also a sphere shaped thing on a pole? Here are more photos.

    i didn't see any cracks but not getting a great view.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images

  13. #13
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    Okay,it looks like I can access the rafters. I only looked from the attic door because I wasn't sure if I can walk up there. It looks like there is a lightbulb on a cord hanging up there and a little platform. Is this normal? Also a sphere shaped thing on a pole? Here are more photos.

    i didn't see any cracks but not getting a great view.
    "I only looked from the attic door because I wasn't sure if I can walk up there."

    Depends - if you have not walked in and across trusses before I would have someone else do it ... there are a few neat photos on this board by inspectors who fell through the ceiling, wouldn't want you posting a photo of where you fell through, would we - or worse, with you in a body cast because of the injuries you received - so I am not going to be the one to tell you that you can walk the attic and trusses.

    That round thing is an antenna.

    (If you are hearing voices - that's the mother ship.)

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  14. #14
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    This is where I think it is. Does anything look unusual from what you can see? I had to really crop the photo to get it to upload.

    heres another photo of the trusses. It does look like one is not aligned with the rest by my novice eye. But wouldn't the other side of the roof also have the same thing?

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Last edited by Catherine Newberry; 02-27-2014 at 05:01 PM.

  15. #15
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Looks like either one or two trusses are set to the right more than the others, or, the roof sheathing is cut lower on the left side in that area than on the right side.

    Either code lead to the ridge vent looking like it is rolling toward the left side when viewed from outside. If you compare the space between the peak of the truss and the top of the sheathing on each side of the same truss to each other, and from truss to truss, you will probably see what I am seeing too.

    That could very well be what you are seeing.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  16. #16
    Join Date
    Feb 2008
    Location
    Caledon, Ontario
    Posts
    4,982

    Default Re: Deflection in roof

    The photos don't reveal anything.

    Could be the H-clip has been omitted where the deck panels butt one another thus the bowing on the roof plain.


  17. #17
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    The differences between the peak and the roof sheathing as shown in the photo.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  18. #18
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    The differences between the peak and the roof sheathing as shown in the photo.
    Yes that is exactly what I was seeing! Is this a misaligned truss then do you think?

    Here is my question then. I will have to live with it for now but when it is time to replace the shingles, can I have the OSB removed there and then add something on that particular truss to get it level with the rest of them. To me, it looks like only one is lower than the rest.

    Thank you again for all your help.


  19. #19
    Join Date
    Aug 2007
    Location
    Memphis TN.
    Posts
    4,311

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post

    Here is my question then. I will have to live with it for now but when it is time to replace the shingles, can I have the OSB removed there and then add something on that particular truss to get it level with the rest of them.
    .
    The sheathing was cut to install ridge vent.
    * from limited info no problems as show.


    Installing Ridge Vent Part 1 - YouTube

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  20. #20
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    I will have to live with it for now but when it is time to replace the shingles, can I have the OSB removed there and then add something on that particular truss to get it level with the rest of them. To me, it looks like only one is lower than the rest.
    The time to address it would be when you replace the roof.

    The problem will likely be that the roofer will not know what needs to be done, a good carpenter or framer should be able to figure out what is not aligned and what can be done to bring it into alignment.

    Doesn't look like it will take much ... not much more than someone with some smarts and experience.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  21. #21
    Join Date
    Aug 2007
    Location
    Memphis TN.
    Posts
    4,311

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    The time to address it would be when you replace the roof.

    The problem will likely be that the roofer will not know what needs to be done, a good carpenter or framer should be able to figure out what is not aligned and what can be done to bring it into alignment.

    Doesn't look like it will take much ... not much more than someone with some smarts and experience.
    Guess that would be one way to address a cosmetic issue.
    *sounds like a lot of expense to fix a roof that is performing.

    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  22. #22
    Join Date
    Mar 2012
    Location
    Lansdale, PA
    Posts
    876

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    The differences between the peak and the roof sheathing as shown in the photo.
    You are not seeing a difference in the trusses. The plates are not evenly positioned.


  23. #23
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Mark Reinmiller View Post
    You are not seeing a difference in the trusses. The plates are not evenly positioned.
    Mark,

    Do you see the differences now? The differences are still there, I just took the truss plates out of play for the mind as the human mind "sees" what it wants to "see", makes things do what it thinks things should be doing, add color where it thinks color should be even when no color is there, etc. ... adding the red "string lines" should allow the brain to unfocus from the truss plates.

    The "string line at peak of each truss actually misses the peak of one truss, but that would have taken too much text in the photo.

    Look at the relative spaces between the peak and the roof sheathing to each side of the peak, it is not the same at each truss or at each side of the peak.

    Ever watch, I think it is called "Brain Games" on TV? Shows that the brain is doing amazing things when those amazing things are really not happening.

    Some of the optical illusions are here: 10 Optical Illusions That Will Blow Your Mind (PHOTOS)

    Look at the image of the building and concentrate on the black dot, the image will change once, yet when you blink, if not before, you will see a third image ... the first and last images are there, the middle image is all in your brain. Pretty cool stuff.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  24. #24
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Jerry,

    Just curious though, how would a misaligned truss like this normally be repaired when installing the new shingles so the sheathing is level?


  25. #25
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    Jerry,

    Just curious though, how would a misaligned truss like this normally be repaired when installing the new shingles so the sheathing is level?
    The side which is set back, probably on the front and what you are seeing, could have a nailer (possibly a 2x4 8 ft long) placed next to the misaligned truse and placed so that the top of it was in alignment with the top of the trusses to each side. The roof sheathing would be nailed to this new wood nailer.

    The misaligned peak of the truss might just disappear in the ridge vent area, and the back side you probably never see.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  26. #26
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    Oh, I see. That doesn't seem like it would be too much extra work if you already were getting your shingles replaced anyway. I guess you would have to remove all the sheathing in that section too.

    i saw some roofing websites also saying you can add shims to level it? Do they mean shims under the sheathing?

    I live in Michigan if you can recommend anyone or can give me an idea what to look for when choosing a roofer for down the road when I get this done.

    You have been extremely helpful. I was glad I was able to get some photos of the area in question.

    BTW my home inspector never responded.

    Thanks again.


  27. #27
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    Oh, I see. That doesn't seem like it would be too much extra work if you already were getting your shingles replaced anyway. I guess you would have to remove all the sheathing in that section too.
    Correct, should not be much extra work.

    i saw some roofing websites also saying you can add shims to level it? Do they mean shims under the sheathing?
    I wouldn't use shims as the panels should be fully bearing on the tops of the trusses and shims would mean that a larger size nail would be needed, and they would not likely have considered that.

    I live in Michigan if you can recommend anyone or can give me an idea what to look for when choosing a roofer for down the road when I get this done.
    Maybe someone here could help, but you would likely need to provide a better location than just "Michigan" as roofers and most contractors are probably more locally oriented and their business probably does not include the entire state.

    BTW my home inspector never responded.
    Apparently not a recommendation to use him or recommend him, or any contractor he may know.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  28. #28
    Join Date
    Mar 2007
    Location
    Spring Hill (Nashville), TN
    Posts
    5,851

    Default Re: Deflection in roof

    Quote Originally Posted by Catherine Newberry View Post
    Oh, I see. That doesn't seem like it would be too much extra work if you already were getting your shingles replaced anyway. I guess you would have to remove all the sheathing in that section too.

    i saw some roofing websites also saying you can add shims to level it? Do they mean shims under the sheathing?

    I live in Michigan if you can recommend anyone or can give me an idea what to look for when choosing a roofer for down the road when I get this done.

    You have been extremely helpful. I was glad I was able to get some photos of the area in question.

    BTW my home inspector never responded.

    Thanks again.
    It's a non-issue. IMVHO, trying to correct it will not improve anything but the contractors will make it sound like the house will collapse if it is not corrected. But hey, if you have the extra money to throw at it then go for it....

    Scott Patterson, ACI
    Spring Hill, TN
    www.traceinspections.com

  29. #29
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    I live in Goodrich, Michigan. I am just looking at the cosmetic side of it and if I'm getting the roof replaced anyway shouldn't I make sure it's level?

    I'm not going to address it until the shingles actually need replacing.

    Thanks!


  30. #30
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Scott Patterson View Post
    It's a non-issue.
    Scott,

    It's a non-issue in what way?

    Structurally? We have all (or at least most of us) agreed on that.

    Cosmetic? You may like blue cars and someone else may hate blue cars, does that mean it is a non-issue if you try to make them buy a blue car? It may be a non-issue for you, but it would certainly not be a non-issue for them if they hated blue cars.

    Not sure where your "It's a non-issue." is coming from.

    It is a big enough "issue" that many contractors try to line the trusses up in the first place ... isn't that an indication that the "issue" is large enough to be addressed when it comes up?

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  31. #31
    Join Date
    Feb 2009
    Location
    Southern Vancouver Island
    Posts
    4,607

    Default Re: Deflection in roof

    First of all. shame on a home inspector who is too busy or too something else to not respond to an inquiry from a past client.

    Secondly, if the truss is mis-aligned, it must be out at the backside as well, or maybe some weird adjustments were made.

    The roof shingles are only 10 years old, so you have quite a few years before the time comes to repair the dip, which we agree is cosmetic in nature. A "shim" for there should actually be a long tapered piece that supports the sheathing full length. That is a job for one afternoon for a skilled builder.
    Alternately, a good roofing crew could possibly lay the shingles so that the dip is more or less hidden from below.

    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

  32. #32
    Catherine Newberry's Avatar
    Catherine Newberry Guest

    Default Re: Deflection in roof

    I did look at the back side pretty closely and I don't see anything on that side. I will look at it again though. It's pretty cold here in Michigan.


  33. #33
    Join Date
    Mar 2007
    Location
    Spring Hill (Nashville), TN
    Posts
    5,851

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    Scott,

    It's a non-issue in what way?

    Structurally? We have all (or at least most of us) agreed on that.

    Cosmetic? You may like blue cars and someone else may hate blue cars, does that mean it is a non-issue if you try to make them buy a blue car? It may be a non-issue for you, but it would certainly not be a non-issue for them if they hated blue cars.

    Not sure where your "It's a non-issue." is coming from.

    It is a big enough "issue" that many contractors try to line the trusses up in the first place ... isn't that an indication that the "issue" is large enough to be addressed when it comes up?
    From the prospective a home inspection it is basically a non-issue. I guess it is a cosmetic issue but not being able to really see it in person, that is difficult for me to say. I see truss homes every single day and the vast majority of have some dips or humps in their roof lines. Some are visible when the daylight hits it just right and some are visible in all types of light.

    Scott Patterson, ACI
    Spring Hill, TN
    www.traceinspections.com

  34. #34
    Join Date
    Mar 2007
    Location
    Fletcher, NC
    Posts
    28,032

    Default Re: Deflection in roof

    Quote Originally Posted by Scott Patterson View Post
    From the prospective a home inspection it is basically a non-issue.
    That, I agree with. That was also where my first few posts were at.

    But the discussion evolved into a way beyond home inspection discussion of "how it might be fixed when the time comes" discussion because it is an issue for her.

    Jerry Peck
    Construction/Litigation/Code Consultant - Retired
    www.AskCodeMan.com

  35. #35
    Join Date
    Feb 2009
    Location
    Southern Vancouver Island
    Posts
    4,607

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    That, I agree with. That was also where my first few posts were at.

    But the discussion evolved into a way beyond home inspection discussion of "how it might be fixed when the time comes" discussion because it is an issue for her.
    It would be an issue with me too. I don't like a roof line that isn't straight. Maybe I'm goofy that way? []
    I will tell the client that there is a dip or a bump there, acknowledge that I saw it, checked it out, it was built that way, not a structural concern. This I do to avoid the call 3 months later.

    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

  36. #36
    Join Date
    Aug 2007
    Location
    Memphis TN.
    Posts
    4,311

    Default Re: Deflection in roof

    Quote Originally Posted by John Kogel View Post
    Maybe I'm goofy that way? [].
    Don't ge me started.

    ***IMPORTANT*** You Need To Register To View Images ***IMPORTANT*** You Need To Register To View Images
    It Might have Choked Artie But it ain't gone'a choke Stymie! Our Gang " The Pooch " (1932)
    Billy J. Stephens HI Service Memphis TN.

  37. #37
    Join Date
    Mar 2012
    Location
    Lansdale, PA
    Posts
    876

    Default Re: Deflection in roof

    Quote Originally Posted by Jerry Peck View Post
    Mark,

    Do you see the differences now? The differences are still there, I just took the truss plates out of play for the mind as the human mind "sees" what it wants to "see", makes things do what it thinks things should be doing, add color where it thinks color should be even when no color is there, etc. ... adding the red "string lines" should allow the brain to unfocus from the truss plates.

    The "string line at peak of each truss actually misses the peak of one truss, but that would have taken too much text in the photo.

    Look at the relative spaces between the peak and the roof sheathing to each side of the peak, it is not the same at each truss or at each side of the peak.
    I was focusing on the plates. I see what you are saying. If they set the one truss back a bit then there should be a slight sag in the roof sheathing all the way down to the eave. Or maybe the truss was manufactured incorrectly. Sistering a 2x to the top chord could even old much of the sag.

    I had to do this for more roof, which had a similar, but more pronounced sag. In my case a portion of the top chord bowed down. Since the roof sheathing end joints were above this truss when I tried shimming I found that the sheathing had bowed and the ends of the sheathing pushed the shingles up and made it look worse. I then waited until I replaced the shingles to sister the top chord and replace the sheathing at that area. It is no longer noticeable.


  38. #38
    Join Date
    Feb 2009
    Location
    Southern Vancouver Island
    Posts
    4,607

    Default Re: Deflection in roof

    Quote Originally Posted by Mark Reinmiller View Post
    I was focusing on the plates. I see what you are saying. If they set the one truss back a bit then there should be a slight sag in the roof sheathing all the way down to the eave. Or maybe the truss was manufactured incorrectly. Sistering a 2x to the top chord could even old much of the sag.

    I had to do this for more roof, which had a similar, but more pronounced sag. In my case a portion of the top chord bowed down. Since the roof sheathing end joints were above this truss when I tried shimming I found that the sheathing had bowed and the ends of the sheathing pushed the shingles up and made it look worse. I then waited until I replaced the shingles to sister the top chord and replace the sheathing at that area. It is no longer noticeable.
    Right, shimming one truss to match the others can be frustrating. If one truss is out of whack, it gets put at the gable end. I've done that myself and still had to shim and trim to make the sheathing lay flat.

    John Kogel, RHI, BC HI Lic #47455
    www.allsafehome.ca

  39. #39
    Join Date
    Nov 2011
    Location
    Oregon, USA
    Posts
    333

    Default Re: Deflection in roof

    I was involved with a similar issue a few years ago. A "less-than-reputable" contractor had installed several trusses with significant misalignment, on a large, complicated room addition to an adult foster care home I was asked to review. This was a major State Human Services project, costing close to $100,000 (big money for central Oregon, but I suspect just peanuts for other parts of the country), and the building's owner was not happy with the way the finished product looked. Unlike the OP's situation, the HSD roof had several visible dips that I measured with a straightedge of just under 2", over runs of barely 10'. The contractor refused to do anything about it, and had already been paid in full. The State brought in a second contractor, and he very satisfactorily corrected the situation by sending 2 guys into the attic to shim the roof sheathing (sistering the trusses top chords), while I monitored and shouted down needed elevation changes from topside with my 10' straightedge. A contractor's "grunt" worked with me to re-nail and hand-seal shingles as we proceeded.

    A note to the OP--don't expect a roofer to make such corrections. Get a reputable carpenter involved.


Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •