How to meet new building code requirements for gutters

By Metal-Era. 

ANSI/SPRI GT-1 testing sets industry standard for gutter systems to make commercial roofs more secure in the wake of high winds 

After two years of development led by the Single Ply Roofing Industry group (SPRI), ANSI/SPRI GT-1 became an official testing standard for gutter systems in 2016. The intention was to make low slope, commercial roof systems more secure. The ANSI/SPRI GT-1 standard improves the security of commercial roofs by creating standardized testing and performance measures for the gutters that secure load-bearing membranes. Metal-Era’s own Vice President of Growth, Brad Van Dam, participated in the committee process approving this standard. Since its standardization in 2016, ANSI/SPRI GT-1 was approved and included as a part of the International Building Code, beginning in the 2021 edition. Read on to learn the details about this standard and what it means today! 

Is it required now? 

ANSI/SPRI GT-1 is vital and – as states adopt the latest building code – increasing required throughout the United States. Though each state controls their building code, there are 21 states that already require ANSI/SPRI GT-1 testing as part of their building code, with four others requiring it at local levels as of October 2024. As other states look to follow, there is wisdom in getting ahead of the changes before it is required by your building code.  

Download a copy of the ANSI/SPRI GT-1 standard from SPRI. 

Where is it located in IBC? 

Like the ANSI/SPRI/FM 4435/ES-1 testing standard for edge metal systems, the ANSI/SPRI GT-1 for gutter systems is in Chapter 15 of International Building Code (Section 1504.5.1). 

“Gutters that are used to secure the perimeter edge of the roof membrane on low-slope (less than 2:12 slope) built-up, modified bitumen and single-ply roofs, shall be designed, constructed and installed to resist wind loads in accordance with Section 1609 and shall be tested in accordance with Test Methods G-1 and G-2 of SPRI GT-1.” 

What's at stake? 

When Hurricane Matthew devastated many portions of Florida, countless businesses and homeowners were faced with damages. In just one example, a 7,000 square foot large box retail building saw substantial damage from 80-90 MPH winds. The cause of the damage was most likely from a loose gutter and/or flashing, which led to the roof covering peeling back. Proper gutter/flashing securement would have resulted in no loss. Instead, the retail store was hit with a $70,000 Repair Cost claim, $1.7 million Content Cost claim and $1.75 million Business Interruption claim, for a total $3.52 million claim paid per insurance. (Source: RICOWI Presentation Slides March 2019) 

How to meet ANSI/SPRI GT-1 requirements? 

With tested gutter solutions sized for every application, Metal-Era can help you understand the ANSI/SPRI GT-1 Standard and update your low slope membrane gutter specifications. Available now, ANSI/SPRI GT-1 approved and backed by a 30-Year, 160 MPH Wind Warranty, Seal-Tite WR Gutter is your go-to solution from 5.25 - 7.75" and Seal-Tite XL Gutter is your XL solution from 8 - 14". 

Also, take advantage of Metal-Era's Gutter Calculator, which not only determines design pressures for ANSI/SPRI GT-1, but also calculates the size of the gutter required for specific projects. 

Original article and photo source: Metal-Era