Test Procedures for roof trusses

[Nancy Salme]

I would like to know more about the roof truss test procedures as specified in 3280.402.
When these roof trusses are tested,it says that the chords must be braced with material or method of construction while doing the test procedures. What happens to the connection or the bracing when finished? If it taken off, if so, wouldnt this defeat the purpose, for the connection left would be end stapled in withdrawal from end grain of wood, in which is a non acceptable method of connection. Can I get somone to elaborate on this for me?
Thank-you

[Roy T. Bonney]

Trusses are purchased by the home manufacturer and certified to meet the standards set forth in 401 and 402 when purchased. That being said, the procedures set forth in 401 and 402 are laboratory style test procedures and in looking at figure A-1 in 402, you will see that a table or the like may be utilized. The idea is to replicate the side walls that will then develop the clear span. In the truss facility the weight is replicated by hydraulics.

[Don Amonson]

I believe you are asking about the King Post attachment method used when testing a truss for inital certification or for random follow up testing during production.
I have personally tested hundreds of trusses for Manufactured Housing under ALL design criteria.( ie: HUD1.75, HUD2.0, HUD2.5, Fleetwood 2.5, UL, and UBC Tested.) Both Destruct and Non-Destruct tests. And never once did I use the attachment method used by the home manufacturer.
We always used three lag bolts thru predrilled holes in the king posts to a 4X4 that simulated the ridgebeam height of the different home manufacturers.
When I questioned the people I worked for about this discrepancy between the rule book and actual practice, I was informed that we were testing the truss, NOT the ridgebeam attachment method.
The type of testing that your are asking about should be covered by the Home Manufacturers Third Party Inspection Agency.
Please contact me if you have any further questions regarding any other test methods or procedures.

[Don Amonson]

I did.

[Nancy Salme]

the trusses I am pertaining to were constructed by end stapling in withdrawal from end grain of wood, utilizing no connections on the joints, therefore all of the joints have pulled away from the top chord. I will send photos to you if you would like to see them for yourself.

[Don Amonson]

I would be happy to review your pictures, and let you know my thoughts concerning your problem.My email is: [email protected]

[Nancy Salme]

Don,
I hope you received the photos. The measurments on this system:
the top and bottom chords are 3/4 inchesthick by 1 1/2 inches wide. The web members are 1 1/2 by 1 1/2 and the verticle uprights are 1 1/2 by 2 1/2. I have been informed by a number of experts that what you see in the photos is not even a roof truss, but a whole lot of junk, or a mess. Can you tell me what it is, if not a roof truss? And how could anything constructed like this ever be utilized in a home?

[Don Amonson]

I worked at a manufacturing plant in Central Oregon, Designing and Testing Trusses for over 12 years.Oct.1988 thru Oct.2001. All that we produced were roof trusse and specialty kits for almost every major home manufacturer on the west coast ie: Goldenwest, Redman, Palm Harbor, Skyline, Marlette, Guerdon, Champion, Kit, Liberty, Fleetwood, Fuqua and a lot more.My job was R&D as well as Quality Control, and I have never in my life seen anything like what you have in the pictures that you sent.They look like trusses that are made for Manufactured Housing, but I don't see ANY nail plates that belong at the joints on each side. It almost looks like they were made prior to the invention of nail plates.I really thought that I could help you, but I have NEVER seen anything like this before. And I have seen a lot of strange stuff in my day. Please let me know what you find out, (if you ever do). And feel free to contact me if you would like.