You can say a lot of things about roofs, and most of them might be true. But one thing that nobody can argue with is that roofs are tops. This statement can be taken in several ways. A roof does for the top of your home. It can also act like a "top" or lid for your home, keeping the rain out. Then, there's the third meaning, which is the one we happen to like the most: roofs are the best. (People say things are "tops" when they really like them.) Since we like roofs so much, we've decided to write about them, and you've discovered the blog where we do that.
Acid can destroy a commercial flat roof. Unlike pitched residential roofs, contaminants don't simply roll off. Instead, acid contaminants collect on the roof surface where they can eventually cause major damage.
Causes Of Acid Damage
Acid damage on a flat roof is often the result of bird droppings. If birds congregate in large numbers on a flat roof, which is often the case with pigeons or gulls, the number of acidic droppings will coat the roof membrane. Birds may congregate more heavily in certain areas, so these parts of the roof will be subjected to even more acidic droppings.
Birds may be the main cause of acid damage to a roof membrane, but they aren't the only cause. Air pollution and acid rain can also lead to acid damage, although this is less common and tends not to build up as quickly.
Problems and Concerns
The main issue with acid damage is that it will eat through the roof membrane. It breaks down the polymers in most standard membrane systems. The membrane becomes brittle and more prone to tears and leaks. The acid also weakens the adhesive so that the membrane seals may fail over time. Weakened seals can lead to a lifting membrane and then leaks.
Even asphalt and bitumen flat roofs aren't immune to acid damage, particularly that caused by bird droppings. The acid will eat into the tar and asphalt, leaving behind small pits. Water then collects in these pits. If the water freezes and expands, the pits can enlarge into holes and leaks.
Available repair options depend on the severity of the acid damage. On membrane roofs, any area that has developed a leak or become brittle must be patched, and seams may require resealing. Severe damage means a new membrane must be installed.
Bitumen and asphalt roofs can be recoated to fill in any damage caused by the acid. Extensive damage, particularly those that have lead to extensive leaking, may require a replacement roof or the application of a waterproof membrane.
Prevention is best. Have the roof washed regularly to remove any acidic buildup. Use a commercial roof service to ensure that washing and cleaning don't lead to any other damage.
You may also need to install anti-bird devices, such as stakes designed to discourage nesting and perching on the roof. Sticky substances and scare devices can also be installed to help keep birds away.
Contact a commercial roof repair service for more help.