March 11, 2020: ASCE-7 Subcommittee meeting on Minimum Design Loads:
By: Mark Guthrie, NADRA Code Committee
Members of NADRA’s Code Committee participated in a call held last Wednesday by the ASCE-7 Subcommittee on Minimum Design Loads. We were there due to a proposal under consideration by this influential group of engineers to add a new load requirement to deck boards.
The proponent was looking to mandate at first a 300 then a 250-pound concentrated load requirement on deck boards based primarily on anecdotal evidence of board failures and the increase in average weight of our population. We feel that this change, if allowed to pass, would result in the tightening of spans between joists, the reformulation and retesting of currently well performing composite and vinyl deck boards at a substantial increase in cost for the customer with little or no appreciable increase in safety.
ASCE respectfully allowed us to speak of our opposition, with much of our testimony spent educating the group on the already strict performance requirements of ASTM D-7032. Some of our time was also spent drawing parallels between this proposed change and the lateral load connectors that were forced into code lacking the sufficient facts or data to support them, only to be watered down in future code and in many cases unenforced.
Ultimately, the Subcommittee voted 8-0 in favor but two members abstained in lieu of more study. In the near future, this item will go to the Main Committee of ASCE for a vote. We will be continuing to be a presence within the process make our opposition known in the hopes that the best and most fact based standards will result.
