If you are a building owner one of your most avoidable recurring expenses is going to be your roof. Wether its repairing leaks, recovering your roof with a new layer or doing a complete tear off there is no doubt that taking care of your roof can be extremely costly.
Thats why it is better to prevent problems from occurring by spending a small amount of money maintaining your roof, rather than to wait until a problem occurs and then be stuck with a much more costly issue.
The thing with roofs is that once a leak starts it causes water to infiltrate your roof system, once this occurs the water in the roof will quickly create more deterioration thereby causing more leaks and damage to your building.
This is how it works water in your roof will freeze in the winter thereby expanding and creating pressure which can pop open seams and create holes. This cycle will happen every time the temperature drops below 30F. So in the winter if the temperature is above freezing during the day and below freezing at night, this cycle will repeat every night until the pressure eventually causes a leak.
During the summer the heat from the sun turns the water in your roof into moisture. The moisture creates air bubbles under your roof system and the hot air/moisture toys to escape by degrading the rest of your roof.
Aside from this a leak can cause thousands of dollars in damages by staining ceilings, causing sheetrock to crumble, causing mold and causing damage to things inside the building.
Now before I explain to you how to extend the life of your roof we first need to understand what causes asphaltic roofs to fail in the first place.
Asphaltic roof systems consist of
1. modified bitumen = these roofs can be torched down or glued down. You can tell if your roof is modified bitumen by looking at the length in between seems. on a modified bitumen roof the seams are 3 feet apart.
2. Built up roofs = these roofs are mopped down using hot tar, you can tell if your roof is a built up roof if it is covered in gravel.
This may come as a surprise to you but the number one cause of roof deterioration is the sun.
The sun destroys a roof in 3 ways
1. Thermal shock = This happens when there is a sudden change in temperature. For example ,on a sunny day the temperature on a roof can reach almost 200F, when this happens the asphalt expands from the heat and gets softer, then at night the temperature rapidly drops causing asphalt roof to quickly contract and harden. This cycle happening over and over again causes stress on your roofing material and causes it to degrade. If this happens enough times it can cause your roof to crack.
2. Heat = Roofing asphalt contain beneficial oils with allow flexibility and longevity, by allowing the material to be elastic. The sun beats on a roof day in and day out and slowly evaporates these oils. This leaves the roof more prone to cracking and failure.
3. UV Rays = Just like the human body can be damaged by UV rays, so to the roof can be damaged by the UV light. After enough time being exposed to UV light the roofing asphalt starts to degrade.
Now that we know the number one cause of roof degradation we can come up with the solution. The solution is simple. Protect your roof from the sun.
The most simple way to do this is to coat your roof in a protective coating. The most popular of these is the aluminum asphalt reflective coating also known as the silver coating.
This coating consists of a asphaltic base with chopped up pieces of aluminum mixed in it. The aluminum flecks in the coating reflect the sunlight essentially acting as suntan lotion for the roof. This results in a coating that helps extend the life of the roof by keeping the heat and UV rays off the roof and preventing the asphalt from drying up and cracking. It is affordable and effective and can also help save AC costs in the summer . The only problem with the silver coating is that it wears off every 3-7 years and needs to be recoated.
Two very important notes about the aluminum asphalt coating.
1. it can only be applied to asphalt roof systems, it is incompatible with single ply roofs like TPO or EPDM. This means that the asphalt and solvents inside the coating will eat away at the single ply membrane resulting in a much bigger problem.
2. Aluminum asphalt coatings are not capable of repairing a roof. Many roofers like to sell it as magic solution coating, they claim that when they apply the coating it will fill in all the holes in the roof resulting in all leaks being stopped and a new waterproofing layer. This is not true, the only use of silver coating is to extend the life of your roof. All existing leaks must be repaired before the coating is installed. Otherwise the leaks will continue.
The second way to protect your roof from the sun is to completely cover your roof in aggregate (gravel, granules or pebbles). This way the aggregate absorbs the sunlight thereby protecting your roof from the heat and the UV rays.
There are 2 ways to do this. The first way, commonly done on Built up roofs, is to have the installation crew manually spread aggregate onto your roof. This is done after the last layer of hot asphalt is mopped on. This way some of the aggregate sticks into the top layer of hot asphalt.
This method is very permanent because unlike a coating it does not wear off. The only issue with the pea gravel method is that the gravel only covers the field of the roof, so any tarred up penetrations that are above the roof level such as the mechanical unit in the picture below is exposed to the sun.
What ends up happening is that over time the tar round the penetrations begin to fail from sun deterioration causing leaks in the building while the field of the roof is still in perfect condition.
The result is that the owner either ends up repeatedly spending money repairing the penetrations or he ends up being convinced that he needs a new roof and he spent money that could have been saved.
The solution is to coat all the exposed tar around penetrations in an aluminum asphalt reflective coating.
When our company was called because of the leak on this building we repaired the leaking area with new material and then coated the entire area in silver reflective paint to prevent future deterioration.
The point here is that if you have a roof that is covered in gravel you can still extend the life of your roof by making sure to protect the tar that is still exposed to the sun. this will avoid leaks developing around the penetrations.
The second way to protect your roof in aggregate is to buy membrane that already has a protective layer of aggregate to prevent deterioration.
roofing manufacturer realized that the roofs last longer they are protected from the sunlight and they began to manufacture modified bitumen rolls that already contain a protective layer of aggregate. here the aggregate is reflective ceramic granules. The granules come in many colors but the most popular are white and black
The ceramic granules work exactly the same as the pea gravel. They absorb and reflect the sunlight thereby protecting the asphalt that s under it. The owner can choose between white granules for states that are hot and want to save money on AC and black granules for states that are cold and want to save money on heating.
Over the years the granules become loose through harsh weather and wear and tear on the roof. Eventullay the roof starts balding and you can visually see that granules are missing. At this point if you want to svae money by extending the life ofyour roof rather then letting it fall into disrepair it is smart to cot our roof in aluminum paint. This will reprotect the balding areas and continue to keep your roof protected from it worst enemy, the sun.
Here is a good example of an old granulated roof that can have its life extended by being coated in aluminum asphalt. without the coating more granules will fall off until eventually the sun will dry up and crack the asphalt roof resulting in water infiltration. Another reason this roof can use a coating of silver is because it has had repairs done with tar. If you look at the seams you can see that someone had repaired this roofs seams using tar. unless the tar is coated it will shrink and crack quickly.
So at the end of the day the lesson we can learn from is that during annual maintenance visits the roof should be checked to make sure that all parts of it are protected from the sun.
If the roof is black it should be coated.
If there is exposed tar from recent repairs it should be coated.
If the silver coating is peeling off after 3-7 years it should be recoated.
If the granules are balding it should be coated.
This may sound extreme but in the long run it will save you money. The price to coat a roof in silver is remarkably cheap, and silver paint can prevent almost all problems that a roof will experience. The only requirement is that the roof be leak free before the coating is applied. A roof thats continuously coated in silver can last practically forever.
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