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View Full Version : Traditional trusses with 2x4 webs and cords on home with concrete tile roof



mark petty
07-17-2014, 04:51 AM
2000 block home with concrete tile hip roof - trusses have all 2x4 webs and cords with typical sized gussets plates, sheathing is 3/4" OSB, trusses space 24" O.C. - a general remodeling contractor was on site who stated he also thought it was odd and said he has seen many in this sub-division the same. All permits pulled and signed off on. No visible adverse conditions, no truss specs on site or available. Every like home I have been in so far has 2x6 top chords with large gusset plates. Any thoughts on this as to if it is okay? Thanks

Garry Sorrells
07-17-2014, 05:33 AM
It boils down to the design of the trusses and what load they were designed to.

Jerry Peck
07-17-2014, 06:25 AM
A 2x6 top chord allows for longer top chord spans, a 2x6 top chord would require more connections with shorter spans - for the same loads.

mark petty
07-17-2014, 06:52 AM
A 2x6 top chord allows for longer top chord spans, a 2x6 top chord would require more connections with shorter spans - for the same loads.

Gary, Jerry thanks for the replies; I'm assuming you meant 2x4's would require more connections with shorter spans.

John Kogel
07-17-2014, 08:14 AM
- - - Updated - - -

Mark, they wouldn't have just laid the tiles on the OSB sheathing. Or would they?
I am thinking there may be 2x4 strapping to help support the weight. But I can't tell from here. ;)

Somebody in that subdivision has the original house plans.

mark petty
07-17-2014, 08:31 AM
- - - Updated - - -

Mark, they wouldn't have just laid the tiles on the OSB sheathing. Or would they?
I am thinking there may be 2x4 strapping to help support the weight. But I can't tell from here. ;)

Somebody in that subdivision has the original house plans.

Good thought John, I also could not tell from reviewing photos on the surface and nothing extra as viewed from the attic. I suspect all is okay because the building department inspectors are pretty good in this area; all inspections passed, CO issued and no visible adverse conditions. I explained all this to customers and to check further as a precautionary measure. Thanks to all for replies.

Jerry Peck
07-17-2014, 03:25 PM
I'm assuming you meant 2x4's would require more connections with shorter spans.

Oops!

Yes, 2x4 is what I meant.

Typing on my phone in NC.

Larry Morrison
07-24-2014, 01:47 PM
Most all of the newer homes here are tile and many are with 2x4 top and bottom cords as well as the webbing. These days without the proper knowledge and a computer program I don't think you would want to guess what the load rating is going to be. One extra cross member (webbing) and or gusset nail plate of a certain size will change the loading allowance. I've also seen top cords with a combination of 2x4 and 2x6 all within the Same Truss. Location of bearing walls can also show a change in the trusses make up.

I know a few guys here that run truss shops and they have said most of the engineered trusses in our area (St. George, UT) would handle tile since the trusses are required and designed to support up to 3 layers of composite shingles. But our Snow Load requirements are not the same as say SLC.

I have had some people ask me if the trusses will handle tile, if they were to re-roof. I always tell them that is above my pay grade the only way to know is to have a truss guy come out and take the measurements needed. They run it through the computer and it says yea or nay.

mark petty
07-24-2014, 02:30 PM
Most all of the newer homes here are tile and many are with 2x4 top and bottom cords as well as the webbing. These days without the proper knowledge and a computer program I don't think you would want to guess what the load rating is going to be. One extra cross member (webbing) and or gusset nail plate of a certain size will change the loading allowance. I've also seen top cords with a combination of 2x4 and 2x6 all within the Same Truss. Location of bearing walls can also show a change in the trusses make up.

I know a few guys here that run truss shops and they have said most of the engineered trusses in our area (St. George, UT) would handle tile since the trusses are required and designed to support up to 3 layers of composite shingles. But our Snow Load requirements are not the same as say SLC.

I have had some people ask me if the trusses will handle tile, if they were to re-roof. I always tell them that is above my pay grade the only way to know is to have a truss guy come out and take the measurements needed. They run it through the computer and it says yea or nay.

Larry, good info for future reference, thanks

Joe Klampfer
07-29-2014, 08:24 PM
In the past I'd only see 2x6 trusses with tile roofs but in the past few years I'm also seeing 2x4 trusses on occasion. When I called the tile manufacturer to inquire if 2x4 was ok, I was told they no longer give opinion on truss size due to some of the lighter weight concrete tiles available.

Since this was a new home, with similar homes going up in the same block (with 2x6 trusses) I recommended buyers agent ask to see the stamped approved drawings showing 2x4 trusses with this roof covering, which the builder was not willing to provide... buyer walked.