Commercial flat roofs with HVAC equipment

While no one has ever identified the nail whose lack caused a kingdom to be lost, it is well known that a poorly maintained roof can prove extremely costly. Occupants complain and eventually when their clothes or kitchen or computer network or collection of files is soaked once too often, move out or blame the property manager for inaction.

With roofs it is often a case of “out of sight and out of mind”. A roof typically receives attention only after leakage has begun to occur by which time a minor repair may have become a major expense. Most of today’s modern roof systems are comprised of layers of various materials including a roof membrane one or more layers of insulation and a vapour barrier. With these multi-layered systems water may have to follow an extended pathway through the roof system saturating layer by layer it reaches the building interior. By the time leakage is reported by occupants large areas of roof insulation may be saturated reducing its insulation value and making roof repairs a major undertaking.

In one instance, CCIG encountered a mechanical contractor who had removed a redundant exhaust fan and left the curb on which it was mounted open. The contractor saw the vapour barrier on the concrete roof deck at the bottom of the curbed opening and assumed that the roof membrane continued under the curb. By the time this error was noted there was  four inches of standing water in the curb and the fiberglass insulation over the entire roof was saturated, and yet there was still no reported leak- age into the suites. The reduction in insulation value of the wet insulation resulted in the buildings heating system being unable to provide adequate heat to the top floor units.

Regular maintenance inspections can help identify minor problems such as cracked caulking or obstructed drains, prior to any significant damage occurring to the roof. As minimum inspections should be completed in the fall prior to the onset of winter in the spring to check for damage from ice and snow and after any major work has been completed on the roof such as mechanical equipment upgrades or modifications. Executing a proper repair is as important as identifying a problem early.

Frequently repairs are made by contractors or maintenance personnel utilizing materials or methods that are not appropriate for the roof being repaired. In many instances repairs are temporarily completed by maintenance personnel applying a cold applied roof patch material purchased from the local hardware store. If this repair stops the immediate leakage proper repairs may not be completed until the leak occurs again.

Contractor gluing down a roof membrane with a torch

A good method for ensuring proper repairs are completed on a roof is to have a repair and maintenance specification prepared. A repair and  maintenance  specification is essentially an owner’s manual for your specific roof system. Like an owner’s manual for a car it lists all scheduled maintenance requirements and details appropriate methods for any required repairs. By providing this manual to a roofing contractor prior to completion of any repairs the contract is provided with a listing of the roof construction permissible repair methods and a listing of any warranties which may still be in effect on various roof components.

If the contractor is informed of all of these items prior to his arrival at the building he can ensure that his workers have the appropriate materials to complete the required repairs and are not forced to improvise. Proper maintenance inspections and proper repairs in combination will provide the maximum reliable service like for you roof system.

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