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View Full Version : different kind of truss system



wes owens
07-09-2009, 08:33 AM
See many truss systems like this?

brian schmitt
07-09-2009, 08:50 AM
wes,
picture 3 looks like a two piece(hat truss) truss. with a steep roof with a wide span the trusses are too wide to haul on the road so they are made in two parts. the main section gets 2x4's nailed to the top cord for the hat truss to attach to as shown. sometimes strapping is used to connect the top cords together and you will see a requirement for roof sheeting to be split on the joint of the two trusses.

Jerry Peck
07-09-2009, 09:09 AM
Wes,

Any way to make those photos smaller? :(

Those photos are so small they are hard to see, but the 3rd photo shots piggy back trusses, one piggy-backed on top of the other, but I don't see any straps or gussets holding them together. :eek:

The other two photos show hip step down trusses with a couple of hip step down trusses missing and the top being conventionally framed instead of trusses. That *may* or *may not* be okay, depending on the truss engineering.

It looks like they might have the OSB oriented the proper way, vertically up the roof with the long edge perpendicular with the supports.

Again, though, the photo are so *small* (and lose resolution when zooming in) they are hard to see much in them.

wes owens
07-09-2009, 09:16 AM
What is the largest I can make the photos?

I tried to download some the other day and it would not do it, so I had to make them alot smaller.

Jerry Peck
07-09-2009, 09:49 AM
Try 600 x 800 or even 1024 x 768.

wes owens
07-09-2009, 09:51 AM
See if this is any better.

Jerry Peck
07-09-2009, 09:51 AM
I downloaded FastStone Image Viewer someone here recommended to bulk change file names and it works well with bulk changing size too. Free download to boot! :cool:

FastStone Image Viewer - Powerful and Intuitive Photo Viewer, Editor and Batch Converter (http://www.faststone.org/download.htm)

Pete Lauterer
07-20-2009, 05:42 AM
Wes,
Trusses of this type are common around here and almost never installed correctly. Make sure there is contact or weight bearing between the upper and lower truss at the ends. The upper and lower sections must be in contact at outside ends. Typically around here the wieght/contact point of the upper trusses ends up on the purlins. According to most manufactures that is a no no.

Roger Hankey
07-20-2009, 07:02 AM
A good resource when examining trusses is the TPI truss installation guide found at Building Component Safety Information (http://www.sbcindustry.com/bcsi.php)
click the view pdf link under the illustration of the cover. I've check it however, and it does not specifically discuss strapping or how the cap trusses are connected to the lower trusses. What I saw discussed was cont. lateral restraints and diagonal bracing. Anyway it is a useful source of information on truss installation do & don'ts.

Jerry Peck
07-20-2009, 08:42 AM
Make sure there is contact or weight bearing between the upper and lower truss at the ends. The upper and lower sections must be in contact at outside ends.

Not always a correct statement.

It depends on the design and loading of the truss and its bearing points. Most that I have seen want the bottom chord of the top truss set directly on the top chord of the lower truss, and, when the correct trusses are installed together, the bearing points line up.

J Moore
07-20-2009, 06:47 PM
Wes.
Middle picture, is that a split truss section?

wes owens
07-21-2009, 04:15 AM
That would be the vertical side of a hip roof.

Those are horizontal boards.