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View Full Version : Attic truss attachment to girder truss



ren ramsey
06-25-2017, 12:33 PM
I saw a truss to girder truss connection that was made with only nails driven through one ply of the girder into the truss that runs perpendicular to the girder truss. Should there have not been a hanger or ledger strip? I usually cant see this connection because of insulation, but in this case I could.
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John Kogel
06-25-2017, 07:03 PM
No doubt, connector plates or brackets would be stronger than a toenail or two.

But the details are in the plans, which were signed off, most likely, by the building official.
Also the builder might argue that the framing was inspected by an authority and was passed.

So good luck with that one, even if you are right to call it out. I have had some success with calling out missing fasteners in an attic, so you never know.

Jerry Peck
06-25-2017, 07:55 PM
No doubt, connector plates or brackets would be stronger than a toenail or two.

But the details are in the plans, which were signed off, most likely, by the building official.

And the way to verify and document that is to look at the approved set of documents at the building department.


Also the builder might argue that the framing was inspected by an authority and was passed.

That would be to no avail as the code itself says that passing final inspection and being given a CO does not make non-compliant items compliant - in fact the code states:
- From the IRC:
- - R110.1 Use and occupancy.
- - - (first sentence = blah-blah-blah) .Issuance of a certificate of occupancy shall not be construed as an approval of a of the provisions of this code or of other ordinances of the jurisdiction. Certificates presuming to give authority to violate or cancel the provisions of this code or other ordinances of the jurisdication shall not be valid.
- - - (two exceptions, neither apply)

Ray Thornburg
07-07-2017, 05:09 AM
I've framed a lot of houses....a hanger is needed here.....

Bill Norman
07-07-2017, 08:24 AM
In order for the truss to be capable of sustaining the intended full design load, it must be properly supported to do so. A few nails are insufficient for large trusses and I see this situation result in failure and collapse under loads of ice, snow, and water on a frequent basis. The IRC requires that truss design drawings must be provided to show Connection Requirements for "truss to truss girder" (R802.10.1) - a Professional knows that this will NOT BE NAILS in a large truss situation. I have never seen truss manufacturers show an end-nailed or edge-nailed connection in truss-to-girder circumstance, and it would be vulnerable to failure.

Also, R801.2 "Roof and ceiling construction shall be capable of accommodating all loads imposed ...and of transmiiting the resulting loads to the supporting structural elements."

If the truss drawings are not available, you might also defer to R802.9 "Approved hangers shall be used for the header joist to trimmer joist connections when the header joist span EXCEEDS 6 FEET". Given that this is true for simple lumber framing, it is reasonable to assume that it will be necessary for wood trusses of similar or greater spans.

When in doubt, recommend that the seller retain a Structural Engineer to certify to the condition.

Thom Huggett
07-13-2017, 03:05 PM
Nails do have a load value, so depending on the span of the trusses being supported there may not be a problem. If there are 3-16d nails per truss in a non-snow load area the supported trusses could span up to 8' and be structurally adequate.

The usual method for supporting trusses is to use hangers, however.

Thom Huggett
07-13-2017, 03:25 PM
Another thing to look at is whether the girder is nailed together. There should be 8d nails at 6" oc on the top and bottom cord and 12" oc on the webs.