Silver Coating/Aluminum Asphalt Paint protecting a roof

Why Silver Coating or Aluminum Asphalt Paint Sealant on Rubber Roofs?

Silver coating or Aluminum Asphalt paint is used to coat  Asphalt based roofs to protect against ultraviolet rays. These roofs are the old Hot Tar roof systems and then also the Modified Bitumen membranes. Both these roof systems are Asphalt based, and the Aluminum Asphalt paint is compatible with it.

The purpose of this Silver paint is to protect the roof against ultraviolet. Aluminum flakes are mixed into an asphalt-based solvent, making it reflective, and that is what gives the appearance of silver.

Watch this video to see how to apply Silver coating to surfaces that need protection against ultraviolet rays.

Explaining Silver coating on how to apply it and what it is used for

Ceramic or mineral coatings and Aluminum Asphalt Paint serves the same purpose

Some Modified Bitumen Rubber membranes come with ceramic granules embedded and there is no need to paint it with an asphalt paint. When the surface is plain or smooth, then it is vital to coat the roof with a silver coat.

Silver Paint or Aluminum asphalt paint is a coating tat is applied over rubber roofs to protect against ultraviolet rays
Silver Paint or Aluminum asphalt paint is a coating that is applied over rubber roofs to protect against ultraviolet rays

Advantages of Silver Coating or Aluminum Asphalt Paint

  • A roof that is coated with this paint on a regular basis can almost last indefinitely. This coating reflects the ultraviolet, and the roof will not be damaged. As long as this aluminum asphalt paint is maintained on the roof, there is no reason why a modified bitumen rubber roof or a Hot tar roof will ever be replaced.
  • Because of its reflectivity, the roof is much cooler. The surface is so cool on a hot sunny day that you could walk on it barefoot without getting burned.
  • Because asphalt or bitumen is an oil based product, it evaporates over time, causing the product to dry, shrink and crack. The combination of being a sealant and lowering the temperatures slows down this process.
  • It would triple the life expectancy of a Modified Bitumen Rubber membrane if it were coated with “silver coating” on a regular basis.

Disadvantages of Aluminum Asphalt coatings

  • need a new coating every 3 – 5 years
  • the surface has to be cleaned and washed every time to paint
  • makes it hard to detect leaks
  • makes it hard to make proper repairs – the paint has to be removed before a roof repair
  • when the building changes ownership, many times people don’t know or forget about the necessary maintenance of a commercial roof

Watch this video about “Silver Coating”  or Aluminum Asphalt paint. The video explains what the coating is for and how to determine what type of roof you have.

Rock instead of Silver Paint used to protect roof against Ultraviolet Rays

The old conventional way of protecting an asphalt roof against ultraviolet rays was to add a layer of stone. This was the best type of protection at the time instead of aluminum asphalt paint. But there was the added cost of bringing the stone up and also the added weight.

Disadvantages were:

  • added cost hauling and spreading the stone
  • added weight putting stress on the structure
  • debris collected in between the rock and promoted plant growth
  • made it difficult to find leaks and make necessary repairs
Gravel or stone was used in the early days to protect a roof from ultraviolet

Partially Aluminum Asphalt Coated Hot Tar Build-up Commercial Roof

Instead of rocks or stone, aluminum asphalt paint is used to protect the commercial roof. In this case, only a part of the roof was coated. The apparent reason was that the roof was leaking in some areas, and they tried to stop the leaks by painting this asphalt sealant on. Aluminum asphalt sealant should never be used to repair flat roofs or fix leaks. It will never work.

Partially coated asphalt roof - They did not do it to protect the roof but rather to seal against a leak

A new coating of Aluminum Asphaltneeded soon

As the image shows, this modified bitumen rubber membrane was coated with aluminum asphalt paint, but it’s been overdue for a new coating. Building owners forget or don’t know that this maintenance is needed and a perfectly good roof gets destroyed by ultraviolet rays.

The silver coating or Aluminum Asphalt paint has worn off. This roof is due for a new coating

Non-Coated Modified Bitumen Rubber Roof

This roof was destroyed by ultraviolet within ten years after installation. The membrane had cracks and started to wrinkle. The cost of maintaining a roof is minuscule compared to that of replacing it.  The problem is that whoever is in charge or not in charge doesn’t know what they do. It is sad to see so many roofs being destroyed because of incompetent management.

The next image shows a close up look of what the surface of the non-protected membrane looks like.

A Modified Bitumen Torch Down roof that was never coated - This one only lasted 12 years

Non- Protected Modified Bitumen Rubber roof full of cracks

Note the cracks that have developed in the membrane due to ultraviolet exposure. The membrane not only cracked but dried up and caused shrinkage. When the membrane shrinks, it will put stress on flashing and the rest of the structure.

See the next image of how the membrane wrinkled and seams were coming apart.

Notice the spider cracks in the membrane - when you see that, then it's too late to do any coating

Modified Bitumen Membrane Wrinkled and Cracked

After prolonged exposure to ultraviolet rays, the rubber membrane cracked and dried up. This layer, in turn, caused the membrane to wrinkle. When the membrane wrinkles, it will put stress on the seams and flashing and start separating causing leaks.

The Modified Bitumen Torch Down roof have shrunken, wrinkled and cracked due to no silver coating or protection

Two Modified Bitumen Rubber Roofs next to each other 

This an image of to commercial roofs abutting with each other. This one is well maintained and coated with aluminum asphalt paint over the years. This roof was installed 20 years ago and is expected to last another 20 years.

The roof on the right has no protection and was installed eight years ago. The membrane already has cracks in it and soon will need to be replaced.

Two identical torch down roofs - One will last indefinitely and the other will need to be replaced in 10 years

Modified Bitumen Rubber membrane with embedded ceramic granules

The best roofing system is one that’s protected against ultraviolet. EPDM rubber and TPO does not come with protection. Modified Bitumen Torch Down membranes come with ceramic granules embedded.

This is the best protection a roof can have. most roofing contractors do not installed the membranes with granules unbeknownst to the owner. They find it easier and less costly to install a modified bitumen membrane with no UV protection.

This is an image of a Torch Down Roof we did 15 years ago. This roof has the ceramic granules embedded as a protection

Embedded Ceramic Granules Protecting the Modified Bitumen Membrane against UltraViolet Rays

This is a close-up shot of what the surface looks like of a Modified Bitumen Torch Down Membrane. The ceramic coating is better than Aluminum asphalt in that it is more permanent. The asphalt paint has to be re-applied every 3 – 5 years.

A close-up look what the ceramic granules look like on a Torch Down Rubber Membrane

Fully protected with Aluminum Asphalt Paint against UV’s

This is what it looks like when a roof is fully protected against UV rays. This roof is coated with aluminum asphalt paint every five years and will last a long time to come.

A good example of a well maintained Torch Down roof - They kept painting it with silver coating so the membrane itself was never exposed to ultraviolets

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