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mathew stouffer
06-11-2008, 06:10 PM
Is toe nailing acceptable in this case or does a tie need to be used in the first two photos. I was questioning if these support anything or if they were simply used to support the ridge during construction. Also is a plate needed at the ridge in the remaining photos. It just looked like a mess. They jammed a piece of osb in there and then nailed it together. Any thoughts

Mat

Ron Bibler
06-12-2008, 03:02 PM
Hey Mat. Im not sure of your area codes. but it look like a poor job just the same. As to the center 2x4 post when i was a young man i did not set temp supports up like that. and if i did do a temp i took it down after the roof was set.

May be some one can add to this.

Best

Ron

Steve Frederickson
06-12-2008, 06:22 PM
It looks like there's conventional framing overframed on top of manufactured trusses. Theoretically, there's no vertical load on the 2x4 "post" under the conventionally framed ridge, but in reality there is some load. This load is being placed as a concentrated load on the manufactured truss. The truss was likely not designed for that. More information regarding the truss design, etc. would be necessary before the recommending removal of the post.

Joe Klampfer
06-13-2008, 07:39 AM
it looks like they've changed the original roof line / profile on the fly with poorly framed conventional lumber. I'd probably write it up as further evaluation needed. What is the roof load ? Is it a heavy wet snow region ? Is the roof covering asphalt shingles or concrete tiles (although concrete tiles usually have spaced sheathing).

Jerry Peck
06-13-2008, 08:28 AM
My thoughts are, based on what is shown in the photo, that at a minimum the vertical supports should be turned 90 degrees to align bearing to bearing (the 2x4 is turned to align with the top chord of the truss and the ridge, not perpendicular to them).

As installed, it creates shear forces which could cause splitting of the 2x4 verticals.

The 3rd, 4th, and last photo are of the same area, and there should be some support connecting the ridge to the top chord of the truss. Is there? Hard to tell, but the 4th photo seems to show some type of shim (OSB?) and nails to the top chord??? Whether or not it is properly nailed is another question.

Evan Grugett
06-13-2008, 08:41 AM
Trusses should not be field altered or cut under any circumstances! I would not be offering specific corrections, or discussing types of forces or load paths in the report (unless I had engineering credentials to do so). A structural engineer specialist, or an engineer from the truss manufacturer, should be brought in to analyze the conditions and to specify the repairs. As it appears that this roof framing was altered and added onto, was this done as part of an addition/alterations to the house that requires permitting and municipal approvals? You should advise the client to obtain any of those sign offs that are required by code.

Jerry Peck
06-13-2008, 08:51 AM
Evan,

I may be missing it, but I don't see any field altered trusses in those photos???

Please advise.

Yes, you are correct, trusses should not be field modified, and broken or damaged trusses need to be repaired in a manner in which the truss engineer (or other engineer) specifies in an engineering letter.

Brandon Chew
06-13-2008, 09:31 AM
Mat,

The short and more general answer is that they have taken an engineered framing system (roof trusses) and some amateur framers (because it is not the work of a "professional") have cobbed some conventional framing onto it. The whole system (trusses and the conventional framing being supported by it) needs to be engineered to do what they are asking it to do. There should be plans, permits, code inspections for this work on file ... if not, I'd recommend that a structural engineer evaluate the roof framing system and design repairs.

There's really not enough info in your post and photos to do a proper evaluation. From what I can see in the first two photos, one big thing jumped out at me. There does not seem to be anything tying the tails of the opposing conventional rafters together. That would make the ridge in the photos a structural ridge, and those support posts necessary to keep the roof from collapsing. As such, the posts should be turned 90 degrees and be full bearing on the ridge and truss as Jerry pointed out. An even bigger problem with those posts is that they are in poor locations -- you don't take a distributed load from the roof deck, turn it into a point load (via the posts) and then transfer that point load to the top chord of a truss without having appropriate web members of the truss directly under that point load to carry the load to an appropriate support below. I can only see one web in the photos -- it's near the front post -- and it is probably not adequate for the conditions, as created in the field, by the conventional framing that was added above it.

Brandon

Evan Grugett
06-13-2008, 10:20 AM
Jerry,

The fact that the trusses are now carrying a "new" conventionally framed roof system is enough alteration for me.

Evan

Jerry Peck
06-13-2008, 11:10 AM
Jerry,

The fact that the trusses are now carrying a "new" conventionally framed roof system is enough alteration for me.

Evan

Evan,

That's not an "alteration" *to the truss*. (Unless, of course, Brandon says differently. :) )

However, as Brandon pointed out, it does change the loading on the truss top chord.

MANY truss installations will have some conventional framing added to them on the site, and the same is specified in the truss drawings ... which we do not have privy to. Thus, we cannot simply state it is incorrect.

That said, though, there are many "obvious" issues with the way 'what was done' 'was done', an 'that' can be stated by the HI.

Evan Grugett
06-14-2008, 07:03 AM
OK, it has just altered (increased) the loading on the trusses.

mathew stouffer
06-14-2008, 07:10 AM
Thanks for all the info. We do get some extreme loads around here and this winter was one of th worst in the last 20 years. If it didn't fail then it is not likely going to, I know that does not make it right. I wrote it up as futher evaluation. It just looked like a mess but the photos don't do it justice. Thanks again.

Mat

Ryan Stouffer
06-14-2008, 08:22 AM
maybe you should wear a tie when you are nailing your toes. have you ever tried that. some people swear by it!

Jerry McCarthy
06-14-2008, 10:14 AM
That roof framing mess looks to me like a contributer to the expression, "wood butcher."

Roy Summerville
06-14-2008, 12:42 PM
It looks like a typical Richmond Home thats there type of framing but it is wrong. The support will not carry the weight over time and thats our job, Not only to look at the house for today But for long term. Roy Summerville
Appraise-It/Inspect-It Consultants of Colorado,Inc

Billy Stephens
06-15-2008, 10:07 AM
maybe you should wear a tie when you are nailing your toes. have you ever tried that. some people swear by it!
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Does it work better than this? :D
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