WAC 296-150C-0880   Windstorm protection -- Provisions for support and anchoring.  (1) Each commercial coach must have provisions for support and anchoring systems that, when properly designed and installed, will resist overturning and lateral movement of the commercial coach as imposed by the respective design loads. Support and anchoring systems can be installed according to the Table in WAC 296-150C-1210 or designed by a professional engineer.

     (2) The manufacturer of each commercial coach is required to make provision for the support and anchoring systems but is not required to provide the anchoring equipment or stabilizing devices.

     (3) The manufacturer must provide printed instructions with each commercial coach specifying the location and required capacity of stabilizing devices on which the design is based.


     Single-Wide Commercial Coaches:

     (4) The provisions made for anchoring systems must be based on the following design criteria for single-wide commercial coaches:

     (a) The minimum number of ties required per side is noted in WAC 296-150C-1210.

     (b) Ties must be as evenly spaced as practicable along the length of the commercial coach. No more than eight feet open-end spacing must occur on each end.

     (c) If continuous straps are provided as vertical ties, they must be positioned at rafters and studs. If a vertical tie and diagonal tie are located at the same place, both ties may be connected to a single ground anchor, as long as, the anchor used is capable of carrying both loads.

     (d) Add-on sections of expandable commercial coaches must have provisions for vertical ties at the exposed ends.


     Double-Wide Commercial Coaches:

     (5) Double-wide commercial coaches require only diagonal ties specified in the table in WAC 296-150C-1210. The ties must be placed along the outer side walls.

     (6) Protection must be provided at sharp corners where the anchoring system requires the use of external cables or straps. Protection must also be provided to minimize damage to roofing or siding by the cable or strap.

     (7) Anchoring equipment must be capable of resisting an allowable working load equal to or exceeding 3,150 pounds and must be capable of withstanding a 50 percent overload (4,725 pounds total) without failure of either the anchoring equipment or the attachment point on the commercial coach.

     (8) Exposed anchoring equipment must have a resistance to weather deterioration at least equal to that provided by a coating of zinc on steel of at least 0.30 ounces per square foot of surface coated.

     (a) Slit or cut edges of zinc-coated steel strapping do not need to be zinc-coated.

     (b) Type 1, Class B, Grade 1 steel strapping, 1 1/4 inches wide and 0.035 inch thick, conforming with Federal Specification QQ-S-781-G, meets the requirements of this paragraph.



[Statutory Authority: RCW 43.22.340, [43.22.]355, [43.22.]360,[43.22.]432 , [43.22.]440 and [43.22.]480. 96-21-146, § 296-150C-0880, filed 10/23/96, effective 11/25/96.]