Bayblock Prime FR — Monoform Primer is now marketed as Bayblock Prime FR.

Bayblock Prime FR — Monoform Primer is now marketed as Bayblock Prime FR.

Monoform Primer: What’s it all about?

Editor’s Note: Monoform Primer is now marketed as Bayblock Prime FR.

How it came about

In 1995, Monolithic began working with UCSC to develop a primer that could be applied onto the inside or outside of an Airform. David B. South, president of Monolithic, had two tasks in mind for this primer. He wanted it to minimize the formation of blisters between the Airform and foam and to act as an adhesive on either side of the Airform. Result: the Monoform Primer.

How it works

Airforms used in the construction of Monolithic Domes and EcoShells are made of polyvinyl chloride (PVC) – a very tough and hard roofing material. In the manufacturing process, chemicals called plasticizers are added to the Airform material that give it flexibility and reduce brittleness.

But over time, these plasticizers can migrate or outgas and damage a coating that has been applied to the Airform. Monoform Primer significantly minimizes the chances of that happening. It actually locks the plasticizers into the Airform. This is especially important when painting over an Airform. Most paint type coatings will release from the Airform if they do not have this primer.

In addition, Monoform Primer works as an adhesive that insures the bonding of the foam insulation on the inside of the Airform.

How it’s applied and where to get it

“Put it on per the instructions – 300 to 400 SF per gal, so thin that you can hardly see it,” says Mike South, who has supervised dozens of Monolithic Dome construction projects. “Thicker is not better.” This primer will go on clear and virtually disappear when dry, but it will be very sticky. Monoform Primer can be sprayed on with an airless paint gun or rolled on the interior or exterior of an Airform.

It’s available in five gallon buckets only through the Monolithic Marketplace.

Note: We first published this article in June 2007.