The requirements in UL 1298 cover roof trusses whose structural properties cannot be determined by standar d engineering calculations. The trusses are intended for installation in manufactured homes.
A product that contains features, characteristics, components, materials, or systems new or different from those in use when the Standard was developed, and that involves a risk of fire, electric shock, or injury to persons, shall be evaluated using the appropriate additional component and end-product requirements as determined necessary to maintain the level of safety for the user of the product as originally anticipated by the intent of this Standard.