Reroof, Recover, Resaturant, & Coating—Roof Replacement & Restoration Options
September 29, 2020
While a solid building envelope maintenance program will extend the ability of your roof and the rest of your building envelope components to keep their contents safe and dry, the fact is that each of these components has a limited effective service life. Depending on the type and the quality of the original installation, for roof systems this effective service life is typically 20–25 years. And since the roof is the thought of most often when considering the components of the building envelope, let’s consider the primary options when a roof is nearing the end of its effective service life:
- Reroofing involves complete removal of the roof system, underlying insulation and flashing components. If your building has a metal, wood, lightweight concrete or tectum deck, some deck replacement may be involved.
- Recovery of your existing roof involves minimal demolition/removal. Basically, the existing roof remains in place and a thin cover board or roof insulation is laid down so a new roof system can be installed over the existing roof. Before choosing the Recovery option, a nuclear scan of the existing roof system is recommended. The scan will detect any moisture in the existing roof and roof insulation. These areas can be marked-off and mitigated prior to recovery.
- Roof Resaturant is a viable option when Reroofing or Recovery are not options. A prepared blend of selected asphalt, mineral fillers and penetrating oils, resaturant can be applied over existing built-up or modified bitumen roof systems. After performing a nuclear scan of the roof and the removal of any areas containing excess moisture, as well as vacuuming any gravel surfaces and applying a specialized primer, the resaturant liquid is then poured onto the existing roof surface at the manufacturer’s specified coverage per square foot. An application of No. 7 gravel is then embedded into the resaturant. After 30 to 45 days, the resaturant and gravel “set up” into what is effectively a new and very durable roof system. Depending on the resaturant manufacturer selected, warranties of 5 to 20 years are available.
- Coatings are applied to existing single-ply and metal roof systems. The existing surface of the roof is power-washed. On metal roofs, seams are covered with an elastomeric flashing-grade material with fabric embedded. The base of roof penetrations is addressed in the same fashion. If there is rust on the existing metal panels, a primer is applied at these locations. The final step is a two-phase application of an elastomeric coating. A “base coating” is applied, followed 48 to 72 hours later by a white “finish coating”. On single-ply roof systems, the application is the same, save addressing the seams in the roof. Again, depending on the roof system manufacturer selected, warranties of 5 to 15 years are available that will cover labor and materials.
Before embarking on any roof replacement or restoration project, always consult a reliable professional consultant or roofing contractor.