It is very likely that the existing deck was horizontally spiked together such that the spikes plus the T&G resistance will enable the deck to act as a diaphragm.
D. Matthew Stuart, P.E., S.E., F.ASCE, SECB
Senior Project Manager
Structural Department
Associate
Engineers and Consultants - CMX
200 Route 9
Manalapan, NJ 07726
732-577-9000 (Ext. 308)
908-309-8657 (Cell)
732-298-9441 (Fax)
mstuart@CMXEngineering.com
From: ken ng [mailto:zy7up@yahoo.com]
Sent: Wednesday, November 18, 2009 1:07 AM
To: seaint@seaint.org
Subject: Can 2x6 T&G roof or floor consider to be a diaphragm?
1. 1. I have a 1945 building and it has 2x6 T&G (2" Vert. and 6" Horiz) roof and the floor is nailed directly to beams at 54"o.c. Can I consider these are flexural diaphragms with 54” existing nail spacing?
2. 2. What about additional floor or roof joists that were added @ 18” o.c. with new nails at 18” o.c. Will this be considered to be a diaphragm?
3. 3. Or ½” plywood shall be added on top of existing 2x6 T&G?
4. 4. The drawing plan called out some live load for Storage in 1945. However the hand created drawing was not so clear to read. I could not read the numbers if it's 50#, 75#, 100#, or 125#. Does anyone know what was the 1945 UBC required for this year?