Non-Destructive Roof Moisture Survey

Early detection and mitigation saves money and avoids aggravation.

Your roof provides protection from the weather.  It keeps the rain and snow out, provides shade from the sun, insulates against heat loss and gain, and protects against the wind.  When moisture gains entry into a roof system, it begins to break it down.  Membranes and underlayment can fail prematurely.  The R-value of insulation is diminished.  The deck and structural components can deteriorate and be stressed by the increased weight of the system.  Mold growth and property damage are other costly problems that can arise from unwanted water entry.

Non-destructive analysis is more sensitive than visual analysis and can detect small amounts of roof moisture before the damage becomes critical.  When problem areas are found, it is often possible to mitigate the damage without replacing the entire roof.

Non-destructive roof moisture surveys allow us to evaluate what we cannot see with a visual inspection.  It allows us to see what is going on in the insulation hidden below the roof membrane and above the deck.  We use this technology to detect moisture in the insulation below the roof membrane.  This can help us find defects in the roof system that are undetectable to the naked eye.  It can also help us isolate areas of an otherwise serviceable roof system for spot repair or replacement.  In some roof replacement instances, there is potential to reuse the insulation, allowing for a significant savings.  A non-destructive roof moisture survey can help assess the feasibility of this plan.

We perform moisture surveys using an Infrared Scanner and/or a Nuclear Moisture Gauge.

Infrared scanning devices detect variation in temperature on the roof surface.  After the sun sets, the roof system will shed the heat of the day.  The dry areas shed heat quickly while the areas with moisture trapped in the insulation retain the heat.  The wet or “hot” areas show clearly on the scanner in opposition to the cooler areas of dry insulation.  An infrared survey is ideal for roofs insulated above the deck and having a dark non-ballasted membrane.  In most instances the survey is performed by walking the roof at night after the system has had a chance to cool.  There are some instances when the survey can be performed from below the roof deck.  Please contact us to discuss your specific roof system.

A nuclear gauge operates on the principle of neutron moderation.  Fast neutrons emitted by the radioactive source are slowed by hydrogen in the roof.  The primary source of hydrogen in most roof systems is water (H2O).  Slowed neutrons are detected and counts displayed are proportional to hydrogen (moisture) content.  This survey is performed by taking readings at regular intervals over the entire roof area to be surveyed.  Typically, a 5’ x 5’ or 10’ x 10’ grid pattern is marked out with paint on the roof.  The grid size can be customized depending on the size, composition, suspicion, and budget of a project.

All employees have successfully completed Troxler® training in the safe storage, handling, and transport of nuclear gauges that meets or exceeds the requirements of both the Nuclear Regulatory Commission and the State of Maine.  Independent Roof Services has a Portable Gauge License in good standing with the State of Maine.

We use test cuts to provide definitive verification of moisture in the roof system.  An infrared camera only looks for temperature variations.  Trapped moisture is the main cause of variation, but exhaust fans, flues, wood blocking, and boiler rooms can show up “hot” on the display.  Nuclear back-up can help rule in/out moisture in most of these instances.  However, nuclear technology can be fooled by normal moisture in wood blocking or thick pockets of asphalt.  Test cuts are used on areas that remain suspicious after a survey or to help establish a baseline for wet and dry insulation values obtained from a nuclear survey.  The cuts are small and patched to industry standard with compatible materials.

Our non-destructive roof moisture surveys include:

  • Report outlining the current roof system, our findings based upon the infrared and/or nuclear survey, recommendations, and cost estimates
  • scale roof plan including all penetrations with areas of wet insulation outlined
  • supporting photographs including infrared images
  • outline wet areas of insulation with spray paint on roof

We can customize the components of the survey and report to best suit your needs.

Inspection & Consulting Services

Independent Roof Services provides a full spectrum of roof consulting services, from inspection and non-destructive roof moisture surveys to repair specifications and roof design.

Independent Roof Services   569 Lawrence Rd. Pownal, Maine 04069   |   Phone: 207-688-4770   |   Fax: 207-688-4779   |