An old or leaking commercial roof doesn't mean that it is time for a complete teardown and replacement. A roof recovery is an alternative that can save time and money, as well as keeping old roofing materials out of the landfill. Typically, a spray foam roof is applied over the existing roof. The key is ensuring your existing roof is suitable for the recovery process.
1. Single Roofing System
There can only be one roofing system currently in place. If a roof recovery has been done in the past, such as applying built-up bitumen roofing over an older membrane roof or installing spray foam over any type of original roofing, then a recovery is not possible. Part of the issue is weight — too many roofing materials may end up weighing more than the roof supports can handle. The other reason is an increased chance for leaks.
2. Dry Insulation
You do not want to recover a roof with extensive leaking and saturated insulation. Instead, the old roof must be torn off so all of the old insulation can be removed and replaced following a thorough structure drying. If the subroof is accessible through the ceiling, insulation can be inspected for dampness easily. Otherwise, the roofer must take core samples or use infrared scanning to determine the state of the insulation.
3. Seam Adhesion
A few damaged seams on an old membrane roof can be repaired prior to roof recovery. Extensive damages, though, mean that a new roof is a better option than recovery. This is because extensive loss of seam adhesion indicates more severe problems with the roof itself, which recovery may not be able to remedy. Further, the seams may continue to fail beneath the foam covering, which can lead to future leaks.
4. Minimal Neglect
As long as the roof has been maintained, with leaks fixed promptly and damages repaired as needed, recovery is an option. If there are major damages, such as many leaks, holes, and crumbling, or extensive acid damage such as from bird droppings, then recovery may not be sufficient to overcome all of these issues. A thorough inspection is needed before recovery can occur.
5. Ample Drainage
A lack of drainage will lead to ongoing problems on any commercial roof. If the issues are minor, such as there are sufficient drains but they are clogged, then cleaning the drains can allow for roof recovery. If, on the other hand, there aren't enough drains, then a teardown of the old roof is needed so new drainage can be installed.
Contact a local roofing service to learn more about roof recovery options for commercial/industrial roofing.
