Four documents, not one
When a roofing proposal says a roof comes with a 20-year warranty, the first question should be: whose warranty, covering what? On a commercial roof in Alberta, coverage can come from up to four sources:
- A manufacturer material warranty
- A manufacturer NDL (no dollar limit) system warranty
- The contractor's workmanship warranty
- An ARCA Warranty Certificate, issued through the Alberta Roofing Contractors Association
Manufacturer material warranty
This is the most basic coverage. The manufacturer warrants that its membrane and components are free of manufacturing defects for a stated period. If the product fails because of a defect, the manufacturer supplies replacement material.
That is often where it stops. Labour to remove and replace the roof, interior damage and installation errors are usually not covered, and some material warranties are prorated, so the value shrinks each year. A material warranty protects against a bad batch of product. It does not protect against a bad installation, which is the cause of most leaks.
Manufacturer NDL system warranty
A no dollar limit warranty covers the whole roof system, materials and labour, against leaks caused by product or installation defects, with no cap on the repair cost. The manufacturer becomes responsible for the roof working, not only for the sheets in it.
Manufacturers only issue NDL warranties when an approved contractor installs a full system of the manufacturer's own components, and when the manufacturer's representative inspects the finished roof. There is usually a fee, built into the roofing price. Terms depend on the system: SBS commonly runs 10 to 20 years, while TPO, EPDM and PVC systems can reach 25 to 30 years.
Manufacturers active in Alberta include Soprema, IKO, Carlisle, GAF, Johns Manville and Sika Sarnafil, each with its own warranty tiers and contractor programs.
Contractor workmanship warranty
The roofer's own warranty covers the installation: seams, flashings, terminations, drains and penetrations. Lengths vary widely, from one or two years to ten or more. It is often the most useful warranty in practice, because the first call for any leak goes to the roofer.
The catch is that a workmanship warranty is only as good as the company issuing it. If the contractor closes, the warranty closes with it. That is the gap the ARCA program was created to fill.
The ARCA Warranty Certificate
The Alberta Roofing Contractors Association has represented the province's roofers since 1961, and its members do about 80% of Alberta's commercial roofing, according to ARCA. Only ARCA members can issue an ARCA Warranty Certificate. On low-slope commercial roofs, certificates are available in 5, 10 and 15-year terms, with the 15-year term limited to commercial work.
The contractor is responsible for years 1 and 2. From year 3, ARCA Warranty Ltd covers the remainder of the term, so the coverage survives even if the original contractor does not.
The certificate is built on independent inspection. An ARCA inspector checks the roof during application against ARCA's Roofing Application Standards, and follow-up inspections are carried out around year 2, and around year 9 on 15-year certificates.
What none of them cover
Even a full stack of warranties leaves gaps. Most commercial roof warranties exclude:
- Hail, wind or other storm damage beyond the limits stated in the warranty
- Damage from other trades, including new penetrations cut without the roofer
- Building movement, structural failure and deck deflection
- Condensation and moisture from inside the building
- Damage from ponding water or clogged drains
- Interior contents, lost business and other consequential losses
- Roofs that have not been maintained as the warranty requires
Questions to ask before you sign
Get answers to these in writing, from every bidder:
- Which warranties are included, how long is each, and who backs each one?
- Is the manufacturer warranty a material warranty or an NDL system warranty?
- Is the contractor approved by the manufacturer to issue that warranty?
- Is the contractor an ARCA member, and is an ARCA certificate included?
- What maintenance does each warranty require, and who keeps the records?
- Does each warranty transfer if the building is sold, and is there a fee?
- Can we see sample warranty documents before we sign?
Comparing warranties across bids
Two proposals can both say 20 years and offer very different protection. A 20-year material warranty and a 20-year NDL are not the same document. Neither is a 10-year workmanship warranty from a company with no third-party backing and a 10-year ARCA certificate.
When you compare bids, put the warranties side by side: type, length, who pays for labour, who backs the coverage after year 2, and what each excludes. If a proposal will not name those details in writing, treat that as an answer.
Keeping coverage valid
Most warranty claims fail on paperwork, not on the roof. Keep every certificate, the as-built roof plan and closeout photos in one file. Book spring and fall inspections and keep the reports. Call the roofer before any trade cuts into the membrane, and record the change. When the building is sold or a new manager takes over, hand the file on and complete any transfer the warranties require.
Talk to us about a warranty package
If you are planning a re-roof or reviewing proposals, we can walk you through the warranty options for your building and show you sample documents before you commit. Our own approach is set out on our warranties page.
