While small, simple roofs may be able to get by with a service call for repair work, more complex roof systems are likely to require a leak evaluation first. This technical service investigates and determines the cause of water infiltration. Many roofing professionals follow ASTM D7053-07 Standard Guide for Determining and Evaluating Causes of Water Leakage of Low-Sloped Roofs.
What to Expect
Expect a two-man crew (or more) to arrive and start asking questions. The on-site facilities manager should be prepared to provide information pertaining to the frequency and location of the leaks, especially if there is a pattern to the occurrences. After all relevant historical information pertaining to past roof services and leaks has been shared, the evaluation starts with a walk inside the building.
The roof technicians will look at any interior staining that has resulted from the leak and inspect the roof deck from the underside to make sure it’s safe to walk on. Now the crew will access the roof and assess its condition, initially looking for punctures or other obvious roof defects.
If necessary, the customer may be asked for permission to conduct a water test. When this test is completed, one crew member will be inside the facility and the other on the roof will use a hose to spray water on the surface in an attempt to recreate the leak. The same methodology will be used if a drain is suspected to be the cause of the roof leak; 5-10 gallons of water will help determine when the drain is unplugged, if an interior plumbing problem is to blame for the leak.
The water test isn’t just for the roof surface, though. Once the roof has been sprayed with water, roof technicians will perform the water test on flashing and lastly, block walls. When the leak is recreated, simple phone or walkie-talkie communication between the interior spotter and man on the roof, lets him know the source of the problem has been found.
What’s Uncovered
Because of the leak evaluation, roof technicians can pinpoint the exact source of the leak, be it a roof defect or faulty flashing, or even a non-roof-related leak source such as a skylight, window, HVAC unit, doorway, or block wall.
When the evaluation is complete, results are reported to the facility manager. The roof technician communicates:
The conditions or reasons for why the evaluation was conducted.
The activities that were performed.
The observations made by crew.
The findings (i.e. the cause of the leak).
Recommendations to remedy the leak.
Without knowing the root cause of the leak, repair isn’t always successful. Investigate first, then repair. It’s the only way to guarantee the leak will be fixed for good.