Replies

1. 
   oldhand | Aug 01, 2015 07:55pm | #1

   more info required....

   Maybe it's just my thick headedness acting up here but I think you need to explain better.

   Parallel or perpendicular to the truss direction?

   If you need to cut a bunch of trusses in two you are in tiger land. They  trickier to cut and support sucessfully than stick framing.

2. 
   deadnuts | Aug 02, 2015 06:53pm | #2

   Modifying trusses will require a professional engineer. Hire one.

1. 
   wmheinz | Aug 03, 2015 12:35am | #3

   Agree 100%

   I agree....engineer required on this whether you are cutting one truss or 10.  Also, this would require a building permit in any place I know of - and they will want to see an engineer's approval as well.

3. 
   BossHog | Aug 04, 2015 06:32am | #4

   You call them attic trusses, and then mention webbing, which implies floor trusses. Which one are they?

   With floor trusses, a repair can usually be designed as long as you have a bearing wall under the ends of the cut trusses.

   With attic trusses - It's not so easy.  The bottom chord is in tension, so it can't simply be headered off.  The truss depends on the continuity of the members for rigidity.  It may or may not be possible.  Depends on the design of the attic, how large the hole is, member sizes, loading, etc.

   If your house isn't too old and you know where the trusses were built, contact the truss manufacturer.  They willl hopefully still have the files and should be able to send them to their engineers for a repair.

   If that's not the case, then ask a truss place for a recommendation for an engineer who is familiar with truss design.  (Not all engineers are)

   In any case, don't believe anyone who tells you just to cut them and header them off.  It's never that simple.  A lot of things need to be taken into consideration in order to get things done right.

   BTW - I have 30 years of experience in the truss industry, so this isn't just casual advice.