A built-up, or BUR, roof is made from alternating layers of felt paper and asphalt tar which are stacked and layered onto the roof deck. While asphalt is completely water resistant, it is not sun-resistant. Over time, the sun can bake out the volatiles in the roof tar, which will render it brittle and prone to cracking. In order to better protect your roof, you should look into protecting your roof with a roof coating. One of the best ways to protect your roof and improve its function is to cover your roof with an aluminum roof coating.
Protecting the Asphalt Tar
An aluminum coating will create a barrier that will help to hold volatiles in your asphalt tar, but it will do much more than that. Asphalt will create a reflective surface. In fact, aluminum can reflect over 90% of the sun's rays. By reflecting the sun's rays before they have a chance to heat up the asphalt tar, the aluminum will prevent the volatiles from separating from the asphalt. This will extend the life of your roof and forestall the formation of cracks. You might think of coating your roof with aluminum as an extra cost, but it can help you to save money in the long run by increasing the life of your roof.
Protecting Your Building
As asphalt heats up, it will radiate the heat it absorbs into the building below. As the sun heats up your building, your AC unit has to work harder and harder just to keep your building comfortable. This increases your costs in two ways: 1) You will pay more to keep your building cool. Aluminum is considered a cool roof coating, and as such will help to keep your building 25% cooler than it would be otherwise. 2) When your AC unit works harder than it should, it wears out sooner, and you have to worry about the cost of prematurely repairing or replacing your AC unit.
Paradoxically, to keep your costs as low as possible, you sometimes have to be willing to pay more when you install your roof. If you are overly concerned about the installation costs of your roof, you might decide to forgo a roof coating, but you will end up paying for this choice over and over. If you go with a roof coating such as aluminum, your roof will last longer, your building will stay cooler, and you will run your AC unit less.