FRSA LEGAL COUNSEL Cotney Construction Law
Self-Adhering Underlayment Issues During Roof Replacement Trent Cotney, FRSA General Counsel, Cotney Construction Law Over the past 15-20 years, the roofing industry has made a significant shift away from traditional asphalt felts to other types of underlayments, including self-adhering direct to deck membranes. In Florida, under the guidelines of the Florida Office of Insurance Regulation, to qualify for a Secondary Water Resistant (“SWR”) discount on your homeowner’s insurance, the underlayment you must use is a peel-and-stick membrane bonded directly to the roof sheathing. While the peel-and-stick products that qualify as SWR can also be installed on top of a layer of felt, only installations that are attached directly to the wood sheathing can qualify for an SWR insurance discount. Thus, it’s possible to use the correct product but install it on top of a layer of felt in a way that still does not obtain an insurance discount because it’s not directly attached to the sheathing. There is nothing wrong with this installation; it just does not qualify for an insurance discount. Use of these peel-and-stick membranes can also present significant challenges when roof removal is required. The Asphalt Roofing Manufacturers Association issued a technical bulletin recommending that if one layer of self-adhering underlayment is in place and cannot be removed without damaging the roof deck, installing a second layer over the existing self-adhering underlayment is permissible. In Florida, this recommendation to leave existing self-adhering underlayment in place may conflict with the Florida Building Code. Specifically, the Florida Building Code Existing Building Section 706.7 requires that when a roof covering on an existing site-built single-family residential structure is removed and replaced, the roof decking must be verified and attached per section 706.7.1. Regarding SWR, Florida Building Code Existing Building Section 706.7.2 states in relevant part as follows:
706.7.2 Roof secondary water barrier for site-built single family residential structures A secondary water barrier shall be installed using one of the following methods when roof covering is removed and replaced: 1. In High-Velocity Hurricane Zone regions: a. All joints in structural panel roof sheathing or decking shall be covered with a minimum 4 inch (102 mm) wide strip of self-adhering polymer modified bitumen tape applied directly to the sheathing or decking. The deck 6
FLORIDA ROOFING | April 2020
and self-adhering polymer modified bitumen tape shall be covered with one of the underlayment systems approved for the particular roof covering to be applied to the roof. b. The entire roof deck shall be covered with an approved asphalt impregnated 30# felt underlayment or approved synthetic underlayment installed with nails and tin-tabs in accordance with Section 1518.2, 1518.3 or 1518.4 of the Florida Building Code, Building. (No additional underlayment shall be required over the top of this sheet.) The synthetic underlayment shall be fastened in accordance with the manufacturer’s recommendations. Although they have many benefits, self-adhering membranes present a significant challenge in complying with these and other provisions of the Florida Building Code if removal cannot be accomplished without damaging the deck. In many, if not most cases, the peel-and-stick membrane has adhered so solidly to the substrate it can not be removed, and replacement of the entire deck may be necessary. In light of this possibility, roofing contractors should take steps to protect themselves from this condition when contracting with owners, in particular through the scope of work provisions in their contract. Most litigated disputes arise out of, or relate to, problems with the scope of work. Often, contractors are seeking payment for extras that were not originally contemplated in the contract. However, the owner may believe that the contract included all roofing work to be performed on the project. In this instance, a roofing contractor who is providing a roof replacement for an owner may encounter self-adhering underlayment that cannot be removed without replacing the whole deck. The roofing contractor incurs additional costs for the deck replacement and seeks to charge the owner for the additional charge. However, the contract does not