Roof Condition Assessments Aid in Repair or Replace Decisiontest

By Thomas A. Westerkamp

May 2013

Deciding whether to install a new roof on an institutional or commercial facility is a complex decision, and it often centers on the potential future costs of maintaining the existing roof. To ensure maintenance and engineering managers have as much information as possible about the state of the roof in question and to make a smart repair-or-replace decision, they can perform a roof-condition assessment.

To succeed, however, the process involves setting parameters for the assessment, understanding assessment costs, scheduling and staffing, and reporting and acting on assessment results.

Looking For Trouble

A building's roof can degrade from a variety of causes, including normal aging of the material, wind, rain, ice and snow loads, building movement or settling, improper design; and natural disasters, such as tornados and hurricanes. Roof-condition assessments help managers evaluate roof material resistance to aging and compare the current condition to history records. They also can help managers develop information to be used in planning to ensure sustainability, optimizing life-cycle cost, and make repair-or-replace decisions.

Before starting the assessment, it is good practice to review history records, the backlog of roof repairs, and thermal images and photos of potential problem areas to highlight improvements needed by comparison. The parameters of the assessment encompass the roofing materials, the accessories, and the installation methods.

Roofing materials to check carefully include the deck, insulation and weatherproofing membrane, while the key accessories include flashing, scuppers, collectors, drains, parapets, and sealants around each penetration through the membrane. The assessment also should check key installation methods and locations — the way the membrane, flashing, scuppers, downspouts and penetrations were designed, constructed, and sealed during construction or repair.

These are the main steps in successful assessments:

• Visually inspect the roof for overhanging tree limbs or loose objects that can plug up scuppers or penetrate the membrane.
• Check for trash buildup on the roof surface, in scuppers, and in downspout collectors and gutters.
• Look for obvious membrane defects, such as punctures, separated seams, and ponding. Even if ponding is covered by the warranty, the building owner can still end up with a large bill for repairs of any components not covered by the roofer's warranty.
• Slide a pick tool along every seam to expose loose seams that are not otherwise visible. Reseal these seams, as well as punctures caused by rooftop traffic, following manufacturer's instructions to avoid future problems.