UL 2218:2018-01 Impact Resistance of Prepared Roof Covering Materials.
1.1 This test method provides impact resistance data for the evaluation materials. For purposes of this Standard prepared roof covering materials units, sheets or panels designed for installation with multiple layers of overlapping rows normally on inclines exceeding 25 percent.
of prepared roof covering are considered to be small such materials installed in
1.2 The test evaluates the effect of impact from the steel ball at locations on the assembly selected to be most vulnerable, such as (but not limited to) edges, corners, unsupported sections and joints.
1.3 This test method does not evaluate the effect of weathering, temperature, aging or similar effects on the impact resistance of prepared roof covering materials. These and other factors, including time, roof slope, roof system configuration and application influence the performance of roofing materials in the field. It is not the objective of this test to address all of these factors.
1.4 The impact energies used in this Standard were derived from (see Appendix A). However, largely due to the effects discussed in direct correlation between the performance of roof covering materials steel balls. Consequently, this test method does not provide a performance under all hail conditions, but does provide a basis for coverings when subjected to the impact energies described herein.
impact energies of actual hailstones 1.3, there is no currently established when impacted by hailstones versus direct basis to compare expected comparison of the response of roof
2.1 Values stated without parentheses are the requirement. Values in parentheses are explanatory or approximate information.
3.1 Representative samples of roof covering material, assembled to test decks as described in Preparation of Samples, Section 4, are to be subjected to the impact tests described in Test Apparatus, Section 5, and Test Procedure, Section 6.UL 2218 pdf download.