Replies

1. 
   Mike_Willms | Mar 22, 2001 03:04am | #1

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   Greg,

   We occasionally encounter this problem with 4' skylights in truss roofs. The specs are up to the truss designer, but typically it's like you said: double up the trusses either side. Usually we get a double girder truss either side (slightly beefier, chords are 2x6 instead of 2x4) and run purlins between up-to the opening. You could header off at the opening and run a rafter between it and the ridge, and from the ridge to the back wall.

1. 
   Boss_Hog | Mar 25, 2001 02:37am | #2

   *In general - If the trusses are designed to be 2'on center, you can use a double truss on each side of a 6' opening, and a triple truss for up to a 10' opening. No need for special girders. Definitely check with local codes and your truss company, though. And don't cut trusses out for skylights, dormers, attic fans, etc.

2. 
   Greg_B. | Mar 25, 2001 02:40am | #3

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   I'm putting a dormer in a trussed roof(i'm used to rafters).I need a 4 feet space for the dormer. Do I just double-up the trusses on each side of the dormer and header it off or is there an easier solution?
   Thanks