Jim, check the free area between the trusses in the unblocked spaces versus
the free area through the architects continuous vents. Unless the soffit is
directly attached to the bottom of the trusses sloping top chord so that the
air passing through the vents cannot move from the blocked space to the next
free space I would think the limit on free area would be at the vents.
SDS Architects, Inc
205 N. Dewey Street
Eau Claire, WI 54703
From: Jim Kestner [mailto:jkestner(--nospam--at)somervilleinc.com]
Sent: Wednesday, June 14, 2000 3:47 PM
Subject: Wood Diaphragm Edge
We typically provide solid blocking in every 3rd space between roof
trusses to bring the roof diaphragm load down to the shear wall. The
Architect says he has to have venting in every truss space and does not
understand why we need this blocking. We suggested that he have a
continuously vented soffit and add venting between the trusses where the
blocking is not required.
I thought about using Simpson H1 clip to help take the load down to the
wall, but then you still don't have sufficient edge nailing on the
Jim Kestner, P.E.
Green Bay, Wi.