Roof designers often incorrectly give considerable weight to a manufacturer’s warranty when considering a roof system and a specific manufacturer. Many limitations are associated with most warranties. The warranty itself should not be the basis for selecting a system or a manufacturer.
Warranties do not stop or protect against leaks. They do not entitle a building owner to a replacement roof if there are manufacturing defects in materials. They do not provide for proactive replacement if a roof is clearly failing and degrading but still not leaking. They do not cover any consequential damages to other building components or contents of the building. They do not provide any coverage for lost time or productivity resulting from a leak. Furthermore, they do not ensure that damage caused by hail or wind, or another type of damage will not occur. Rather, a warranty most typically provides for limited repairs of the roof membrane only after a leak occurs. Legally, a warranty defines specific rights and obligations of the building owner and warrantor. It includes remedies and exclusions. If the warrantor is out of business when a problem covered by the warranty is experienced, the warranty often becomes a useless piece of paper.
Since the 1970s, many warranties have become marketing tools rather than true reflections of demonstrated roof system performance. It is common to see 20-year warranties on roof systems that have only been in the marketplace for a few years. When architects rely on warranties for performance, rather than paying attention to the factors that actually affect performance; the potential for premature failure dramatically increases.
When warranties are specified, the specification typically requires the warranty to be issued by the roof membrane manufacturer. It is recommended to specify that the warranty include both the roof membrane materials, other roof system components such as roof insulation, vapor retarders if used, fasteners, adhesives, flashings, and accessories. The warranty should cover the roofing contractor’s workmanship. Material-only warranties are also available from manufacturers. In fact, it is nearly impossible to buy roofing membranes without at least a materials only warranty. However, these warranties are nearly useless. A manufacturer’s warranty establishes a direct contractual relationship between the building owner and manufacturer. For low-slope systems, the length of coverage for a manufacturer’s warranty is typically 5 to 25 years, with 10 years being the most common.
Warranties will be prorated in value unless they are clearly specified as a NO DOLLAR LIMIT (NDL) warranty. Prorated warranties provide very limited coverage in the later years of the warranty period just when the warranty coverage is most needed.
When involved with landscaped roofs, consider warranties that cover the cost of removing and replacing the overburden of the landscaping to access the roof. Reliable, hot-applied rubberized asphalt membrane roofing manufacturers will provide these.
A warranty may have some merit if it means that the manufacturer will take steps to minimize the potential for future problems (such as reviewing the specifications and details and providing meaningful inspection during application). A warranty may also enhance the likelihood that a professional contractor will install a roof. However, rather than relying on a warranty to obtain a qualified contractor, designers should specify contractor qualification requirements as discussed in the next section.
If a problem that is covered by the warranty occurs, and the warrantor is still in business, the presence of the warranty may lead to a quick resolution of the problem. Virtually every warranty issued by a manufacturer covers repair of leaks caused by defective materials and workmanship (if the warranty is not for materials-only) provided that the cause(s) of the leakage is covered under the terms of the warranty. Without a warranty, the Owner might have to pursue legal action to obtain relief. Pursuing legal action may be too costly if the problem is small. Also, the presence of a warranty provides a direct avenue for the Owner to purse a claim with the manufacturer if the manufacture does not respond to a problem covered under the warranty.
Warranties are normally prepared to limit the manufacturer’s liability to a narrow scope of provisions rather than to provide protection for the building Owner. Warranties typically preclude claims based on other theories of liability, including negligence and breach of contract. In addition, warranties typically exclude the implied and express warranties established by the Uniform Commercial Code.
Warranties are almost always provided in standard language provided by the manufacturer’s legal department and changes or deviations are extremely difficult. It is important to evaluate warranty coverage as part of the criteria to select the roofing material manufacturer before specifying. Most warranties contain several unfavorable provisions, the most significant being:
- Exclusion of consequential damages (including damages to building interiors and contents, and business interruption)
- Limitation of wind coverage to wind speeds that are typically well below the design wind speed prescribed in the building code. Coverage limited to very low wind speeds sometimes listed as only a “gale”, which can later be interpreted to exclude any damages from winds exceeding 31 mph.
- Exclusion of hail damage (see Figure 13)
- Limitation of leak repairs to patching the membrane rather than removing and replacing wet insulation
- Only the manufacturer can determine the applicability of the warranty
- Inclusion of several provisions that could result in the building owner’s inadvertent nullification of the warranty.
- Unreasonable limitations on the owner’s right to make emergency repairs without voiding the warranty.
- Unrealistic requirements (often in very fine print) for meticulous record keeping and maintenance.
Complete voiding of the warranty if an “unapproved” roofer makes even a small modification.