ANSI/SPRI/FM 4435/ES-1 (ES-1), "Wind Test Design Standard for Edge Systems Used with Low Slope Roofing Systems," is a standard addressing wind resistances testing of edge metal systems, except gutters, used to secure the perimeters of low-slope membrane roof systems.
The International Building Code contains a specific provision requiring specific edge metal flashing design to be tested using ES-1. For example, in the International Building Code, 2018 Edition, this provision reads as follows:
"1504.5 Edge securement for low-slope roofs. Low-slope built-up, modified bitumen and single-ply roof system metal edge securement, except gutters, shall be designed and installed for wind loads in accordance with Chapter 16 and be tested for resistance in accordance with Test Methods RE-1, RE-2 and RE-3 of ANSI/SPRI ES-1, except V, shall be determined from Figures 1609.3(1) through 1609.3(8) as applicable."
ES-1’s 2011 Edition is applicable to IBC 2018.
In addition to the code requirement, ES-1 also is sometimes referenced in project specifications as a specific requirement for edge-metal flashings.
ES-1 consists of two primary parts. The first part provides an analytical procedure for estimating the design wind loads that will act on the perimeter edges of low-slope roof systems. The second part provides three test methods—RE-1, RE-2 and RE-3—for evaluating the wind resistances of specific edge-metal system designs. The fundamental concept of ES-1 is the tested wind resistances of a specific edge metal system need to be greater than the design wind loads for the specific building being evaluated.
IBC 2018 does not adopt or utilize ES-1’s design wind load determination procedure. IBC 2018 requires design wind loads be based upon IBC 2018’s Chapter 16-Structural Design, which references ASCE 7-16, “Minimum Design Standards and Associated Criteria for Buildings and Other Structures,” as its basis for design wind load determination.
Customarily, design wind loads for buildings are determined by the project designer. IBC 2018 Section 1603.3 requires design wind loads be indicated in the project’s construction documents.
Wind resistance values for specific edge-metal flashing profiles typically are provided by manufacturers of edge-metal systems. Project designers should include in their designs specific edge-metal systems that have wind-resistance values suitable for the specific building design.
To provide for building code compliance of shop-fabricated edge-metal flashings, NRCA has conducted extensive testing using ES-1 of various edge-metal flashing profiles. The edge-metal profiles tested are based upon the construction details contained in The NRCA Roofing Manual.
NRCA also maintains separate certification programs with Underwriters Laboratories Inc. and Intertek Testing Services, N.A., based upon the ES-1 testing we conducted. These certification programs provide third-party verification of compliance with ES-1 by code-approved testing agencies. Although such third-party verification is not a specific requirement of IBC 2018 and may not be required by project specification requirements, it does provide credible, independent means of showing edge-metal flashings fabricated in a sheet metal shop comply with ES-1. Additional information about these certification programs is accessible by clicking on the links below.