Modified bitumen, also sometimes known as torch down roofing, is a popular choice for many low slope roofing applications. With a relatively low cost and a long history of success, it can be a beneficial choice for many building owners. Modern varieties even use reflective roofing granules to ensure a cool surface temperature, which helps reduce cooling costs. However, it is not perfect for every location, as it has poor resistance to ponding water.


A small apartment building in Colorado had an aging torch down roof with leaks in several units. A previous contractor used a store-brand acrylic in an attempt to make the roof watertight again.

After multiple applications, the roof still leaked and the owner had to consider full tear-off and replacement. When they met a Castagra Certified Applicator, they found out that there may still be a chance to prolong the life of the roof using Castagra’s Ecodur roof coating.


With extreme adhesion, strength, and the ability to bond to dissimilar surfaces, Ecodur was the perfect product for coating the roof deck, as well as tying in the large amounts of penetrations.

Made of sustainably sourced castor oil and gypsum, Ecodur is VOC free and does not create a breathing hazard for the tenants below. Also commonly used for tank linings, Ecodur is impervious to ponding water.

Application Results

Because Ecodur generally does not require pressure washing, the contractor was able to prepare the surface without risking further damage. The entire surface was swept and blown, and a wire brush was used for any caked-on dirt or debris.

In less than a day, the entire roof, penetrations, and parapets were coated with a monolithic waterproofing membrane that is extremely resistant to water, UV, hail, and anything else the weather can throw at it.