GacoRoof roof coating--BEWARE!
More than a year ago, while the 6 year old EDPM roof did not appear to have any defects, a tiny but persistent leak into the right front portion of the closet developed. I took the trailer several times each to two separate RV Service Centers where they used specialized equipment and skills to locate and fix the leak. The leak continued.
I began to think of roof coating as a possible fix, and on October 6, 2012 went to Hammond Lumber in Brunswick ME to look into roof coatings. I was shown a product called GacoRoof, which was said to be good for more than a dozen types of roofs including “Flat Roofs, Mobile Homes, RVs and Campers”. “Limited 50 Year Warranty”, “Do it yourself in a day”, “No special equipment necessary”.
I researched the product on their website, found references to two types of coatings:
SINGLE COMPONENT SILICONE COATING
SINGLE COMPONENT SOLVENTLESS
I studied an article on rubber roof care by a trusted author in my January/February Escapees RV Club Magazine which contained the following warnings:
• Caution: Do not use petroleum distillates to clean the
roof as they may cause permanent damage.
Caution: It is important to not use cleaners or conditioners containing petroleum products, hard abrasives or citric* based formulas.
Use of these products may cause irreparable damage to your roof and/or void the warranty.
FREQUENTLY ASKED QUESTIONS
Q. If I use a roof treatment product containing petroleum distillates on my rubber roof, will that void my warranty?
Q. If I buy a used RV and it has a rubber roof, how can I tell if the previous owner used petroleum distillates and damaged the rubber roof? What should I look for?
A. Two things: first, swelling and uneven thickness of material. Second, loose areas. Petroleum distillates soak in and cause the adhesion to loosen and the membrane to balloon. When the ballooning goes down, the membrane may never adhere properly or completely.
There is no level of petroleum distillates that is recommended.
During the week of October 8, I returned to Hammond Lumber to read the fine print on the container and to inquire about the possibility that the Solventless Coating might be necessary. I was introduced to the GACO representative, Mike McGovern, who happened to be in the store at the time. I showed him the Roof Care article and read the solvent warnings to him. He said the solventless coating is only marketed in California, not for performance issues, but to meet their higher air pollution standards. He assured me that all GACO roof coatings are safe and appropriate for EDPM rubber RV roofs. He went on to say that if the RV was to be driven on highways a primer would be absolutely necessary to assure that the roof coating would adequately adhere to the underlying EDPM.
I contracted with an experienced professional roofer, who has remained in frequent contact with the GACO rep for guidance, and we waited for a stretch of good weather. I scrubbed and rinsed the roof and it was rinsed several more times by rain.
On Wednesday, October 17, 2012 the primer and the first coat of coating were applied. The next day, there were several bubbled areas on the roof. They are not tiny bubbles, measuring ½ inch high and some are about 2 feet in length. The bubbles are not in the roof coating, but are within or underneath the EDPM.
It appears then, that the GACO products did indeed cause ballooning of the EDPM and has seriously damaged the roof.
The remainder of the job has been postponed pending good weather and additional consultation with the GACO rep.
October 21, 2012
Roofer cut away the GACO sections that were not adherent, meticulously cleaned and dried the affected areas, used a brush to cover the forward ¾ of the roof with GACO roof coat.
October 23, 2012
Roofer cut away more GACO sections that were not adherent, applied GACO roof coat to entire roof with brushes and rollers.
July 1, 2013
Roof replaced with new EDPM.