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. Read more.