SPRI, the association representing sheet membrane and component suppliers to the commercial roofing industry, has announced that it has completed its review and revision to ANSI/SPRI VR-1, Procedure for Investigating Resistance to Root or Rhizome Penetration on Vegetative Roofs, and the test standard has been reapproved as an American National Standard. This test standard was developed to test the ability of a root protection barrier to prevent root penetration through the waterproofing layer on low-slope single-ply membrane and coated roofs. The standard was first approved as an American National Standard and was published in 2011.
Vegetative roofing systems are becoming a more popular option due to storm water retention and other reported benefits, such as reducing the urban heat island impact. This test method, which evaluates the ability of a roofing material to resist normal root or rhizome penetration through a root protection barrier or waterproofing layer, is an important tool in designing a vegetative roof system that will provide long-term performance without leaks due to root systems penetrating the waterproofing layer.
SPRI also announced that it is revising ANSI/SPRI WD-1, Wind Design Standard Practice for Roofing Assemblies, and plans to canvass the document for reapproval as an American National Standard. ANSI/SPRI WD-1 provides a methodology of designing for wind uplift resistance of non-ballasted built-up, modified bitumen, and single-ply roofing system assemblies installed over any type of roof deck. The proposed revision will update the standard to incorporate the design pressure calculation changes contained in the American Society of Civil Engineers (ASCE) document, ASCE 7-16, Minimum Design Loads for Buildings and Other Structures. These revisions will be beneficial to every roofing professional who uses ASCE for determining wind loads on structures. SPRI developed the ANSI/SPRI WD-1 standard as a reference for the design, specification, and installation of ballasted single-ply roofing systems. It was last revised and reaffirmed in 2014.