Roof Management Plan: Testing Your Roof for Moisture

We work with many building owners and maintenance managers who find they suddenly need to repair their building's roof and lack the funding to get it done properly. One of our clients has been working on finalizing the proposed roofing project for nearly two years. It is safe to say that a Roof Management plan for your building is important to have in place, and even though it may not guarantee funding will always be available it will provide you with solid, up-to-date evidence to provide to the proper decision makers.

In our last post we skimmed over what is considered a beginning to a good roofing management plan. In this post we will talk more about roofing inspections and how detecting moisture is determined.

There are three types of non-destructive methods for testing moisture problems which have advanced over the years to give pretty reliable results: Impedance/Capacitance, Infrared and Nuclear. However, once moisture has been determined by one of three ways is it important to undergo a core test to verify the conditions. 

Impedance/Capacitance - can be done with a hand-held meter by setting it over the roof membrane. It will determine if a specific area in the roof is wet or dry through electronic signals. This testing cannot be completed over wet or ponded areas.

Infrared - Conducted with an infrared camera used after sunset to identify temperature differences on the roof. Areas that are dry will cool off quicker than areas that hold moisture.

Nuclear - A nuclear scanning meter can test in areas of ponding water and scan up to 7 inches in depth of the roof. In the article, "Technical Details: How to Properly Determine Moisture Content in Roof Systems" author John D'Annunzio says "Testing is conducted over the entire roof area by sectioning the roof into grids . . . and recording the readings at each of these locations."

Moisture Verification: Core Cut and Test - In this process you actually drill through the entire roof and extract a core sample. After the core area is properly repaired the sample is tested to provide data of all components found in your roof. Each roof system and repair method can be identified as well as the percentage of moisture detected. Results are them provided and a plan for repair or replacement can begin.

Sources:
Article in Roofing Contractor Magazine