Mike Silvers, CPRC, Owner, Silvers Systems Inc. and FRSA Technical Director - November 2026
Last month’s column (October 2026 FRM) titled “Uncertainty Surrounds New FBC Requirements for Metal Hip and Ridge” discussed that issue in detail. This month, we will look at underlayment changes for all steep-slope roofs (2:12 and above) and the new requirements for asphalt shingle hip and ridge. The code sections referenced are included for both the Residential and Building volumes. The new code has an effective date of December 31, 2026.
First, let’s look at the underlayment changes that impact all underlayment on steep-slope roofs. The new language requires that underlayment lap over hips and ridges a minimum of six inches unless a ridge vent is being used. Since this new language is in the controlling scope language in the code sections, this requirement applies to all types of underlayments used in all steep-slope roof covering types. What isn’t specifically called out is that the overlap should be installed on both sides of the hip and ridge. When one considers the thickness of two layers of self-adhering polymer modified bitumen underlayment or four layers of
ASTM D226 Type II or ASTM D4869 Type III, Type IV or ASTM D8257 nailed underlayment at these locations, then longer fasteners may be needed. As shown in R905.2.5 and 1507.2.6, boxed text, fastener length must penetrate through the roofing materials and not less than 3/4 inch (19.1 mm) into the roof sheathing or, where the roof sheathing is less than 3/4 inch (19.1 mm) thick, the fasteners shall penetrate through the sheathing. This requirement is included for basically all roof types installed over wood decks for both underlayment and roof covering fasteners. This is often missed when used under ridge cap ventilation where, because of a direct opening into the interior, attachment is critical.
Next let’s look at the new requirements for asphalt shingle hip and ridge. Much like the previously mentioned new metal hip and ridge requirements, the changes in asphalt shingle hip and ridge were driven by multiple reports of failures by the Federal Emergency Management Agency (FEMA), the Roofing Industry Committee on Weather Issues (RICOWI) and the Insurance Institute for Business and Home Safety (IBHS) over many post-hurricane mitigation assessments. The asphalt shingle change offers two different compliance paths.
Hip and ridge products must comply with the wind test requirements in UL 2375 modified to use a wind speed of 110 mph. The shingle packaging must also bear a label to indicate compliance with the modified version of UL 2375.
The second path is a prescriptive alternative for attaching hip and ridge shingles. Prior to installing each hip or ridge shingle, two minimum 1-inch diameter spots of roof cement complying with ASTM D3019 or ASTM D4586 or other adhesive specified by the hip or ridge shingle manufacturer, shall be placed on each side of the hip or ridge. The spots shall be placed near the leading edge and fully covered by the exposed portion of the hip or ridge shingle.
Some shingle manufacturers offer hip and ridge shingles made specifically for that purpose that meet the UL 2375 standard but it is apparent that others do not. Even for those who do meet the standard, a question remains: do they indicate compliance on their packaging? If not, then a contractor may need to use the prescriptive alternative. That path will also be used when cutting hip and ridge from 3-tab shingles. Using this path by applying “spots” on the leading edge of the hip or ridge shingle is similar to the “tabbing” method used on extremely steep shingle applications. For this method to add to the uplift resistance, the contact area must be at least as large as the 1-inch diameter on both surfaces. Hopefully, this method can quickly be replaced by material options that are UL 2375 compliant.
The concrete and clay roof tile industry faced many of these same hip and ridge concerns several decades ago and, for the most part, have addressed them and the industry has adapted. It is clearly time for other roof systems to do the same. I have an abundance of faith that, with time, this will happen.
Mike Silvers, CPRC is Owner of Silvers Systems Inc. and is consulting with FRSA as Director of Technical Services. Mike is an FRSA Past President, Life Member and Campanella Award recipient and brings over 50 years of industry knowledge and experience to FRSA’s team.