Alligatoring is the term used to describe the roof condition pictured above, mainly because it looks very similar to an alligator’s hide. Appearing on smooth-surfaced built-up membrane roofs, the shrinking and cracking of the surface bitumen is often due to ultraviolet radiation and the subsequent embrittlement of the membrane. Alligatoring also occurs on some coatings. The pattern is made up of cracks in the surface. The cracks sometimes extend through the surface bitumen or coating. The cracks split, allowing moisture to enter the roofing system. The moisture can travel throughout a flat roof, which can cause leaks located far away from the actual source of entry. Water, as we know, expands and contracts as it freezes and thaws. As this occurs underneath the roofing surface, the cracks will grow in size. As the surface fails, the underlying felts become exposed and brittle. Roofing system failure follows. Water damage is accelerated in areas which also contain ponding water.
Water remaining on your roof for more than 48 hours after a rain ends is ponding water by definition of the National Roofing Contractors Association. This remaining water is one of the most damaging things effecting the life cycle of a flat roof. Even when code requirements are met, some slope is lost due to components suspended from the roofing joints and roof top equipment such as HVAC units. Ponded water can invade the roofing system through any imperfection, no matter how slight. Imperfections like alligatoring (or checking), splits, cracks, fish mouths, bare felts, or an unsealed lap or seam are all risk factors. If the moisture reaches the insulation this can result in rotted organic fibers, weak binders, and reduction of thermal resistance.
How water is removed from a roof is as important as the product selected to protect it. LaFerney Commercial Roofing uses only approved materials to complete each roofing project. Drains are a frequent source of leaks. The use of approved materials ensures cohesion among the elements,eliminating the risk of complications due to incompatible products. All liners for the drainage components are made from reinforced membrane and prefabricated for water tightness that lasts. The prefabrication eliminates welds performed on the roof. The circular drain features a double-weld boot for optimal leak protection.
Plants can grow on roofs. This occurs when dirt, debris, and moisture all come together. Gutters are a frequent location for this. The organic growth can attract birds to nest. Birds carry seeds which can lead to more organic growth. Organic growth is a problem because the plant roots can penetrate through roof membranes or separations in metal panels. As the roots grow, the openings get larger. Once the plant dies, holes are left where the roots once were. Cleaning gutters and trimming back trees are good preventative practices.
Strong wind, snow, heavy rain, straight line winds, tornadoes, hurricanes, and other weather activity can damage roofs. Often this damage requires repair or insurance claims. A roof should be visually inspected following any severe weather event. This is an opportunity to prevent more severe damage. Wind or hail damage can be more severe, with most damage caused by flying debris. There is always a chance storm damage may require emergency repairs. Keep the number of a trusted and licensed contractor on hand in case you have this need.
A client of LaFerney Commercial Roofing had a fire at one of their facilities. Thankfully, they experienced no injuries and only minor damage. The roof damage was mitigated due to the inherent properties of the single-ply membrane installed by LaFerney Commercial Roofing. The roof system recommended by LaFerney met the requirements for a Class A fire rating. The roof damage was quickly repaired by our crew, leaving our customer operational and safe again. Our in-house burn test video demonstrates the fire retardant properties of the PVC membrane installed on this roof.