Mer-KoTM Weather Deck
“ONE HOUR” ASSEMBLY ADDENDUM

FOR SPECIFIERS
When a One Hour fire rating is required, the following should be added to the standard Mer-Ko Weather Deck Specification under INSTALLATION:
Prior to the installation of the Weather Deck System, install Mer-Ko Underlayment providing slope to drain as necessary (minimum 1/4" per foot) and allowed to dry.

THE ABOVE ASSEMBLY IS LISTED AS A “ONE HOUR” FIRE RATED SYSTEM (ICC-ES REPORT NO. 3389) * NOTE: All work shall be installed in strict accordance with manufacturer’s specifications and local building codes using the standard of care for exterior waterproof deck applications.

One-Hour Fire-Resistive Construction The Mer-Ko Weather Deck Fire-Retardant Walking Deck covering installed in accordance with this report over 5/8" thick (15.9 mm) exterior-grade plywood with 2" x 8" (51 mm x 23 mm) joists spaced 16" (.406 m) on center, with all plywood joints blocked, may be substituted for the double wood floor described in Footnote 13 of table 7-C of the UBC. When installed over nominal 2-by-8 joists, the design bending stress assigned to the joists shall be limited to 78 percent of the UBC described designed values.