Up until the early 1980’s, most fire doors were manufactured either using asbestos boards, fibre-cement boards or mineral fibre as their core. Around this time they were all soon found to be problematic in their own different ways. Asbestos, of course, was found to pose major long-term health risks and fibre-cement boards or mineral fibre were far too heavy and difficult to construct.
In response, a vermiculite-based homogenous core was developed and it had since become the industry standard of excellence for fire doors. With reduced manufacturing complexity and cost, and no known OH&S issues, it is the passive fire protection material of choice. Let’s take a look at vermiculite fire doors.
What Does Vermiculite Do?
Vermiculite is an incredibly versatile material in building and construction, due to its fireproof properties, which make perfect for use as a loose-fill insulation or for fireproofing structural steel. It is also used as a packing material because of its absorbing properties. Automotive industries use it in brake pads because of its thermal resistance. However, vermiculite has become best known for its use as the core of fire doors.
Vermiculite is a hydrous phyllosilicate mineral. It is light, inert, and inorganic and makes for excellent insulation. Exfoliated vermiculite retains moisture very efficiently, and in the event of a fire this moisture turns to steam which has a cooling effect on the door and door frame. It also expands into worm-like strands when heated (a process called exfoliation), which impedes combustion and delays the spread of fire. It also has excellent soundproofing qualities and is commonly used in acoustic doors.
On top of its versatility, vermiculite is extremely durable and will not crack or rot over time, making it an optimal choice in building and construction.
The Benefits of Vermiculite
The History of Vermiculite
The first documented experimentation with vermiculite and its unique properties date back to 1824, when Thomas H. Webb experimented with it in Worcester, Massachusetts. It was Webb who gave the mineral its name because he thought the strands that appeared when the it was heated looked like a mass of small worms (vermiculite is a composite of the Latin word ‘vermiculare’, meaning “to breed worms” and the suffix ‘ite’, meaning rock or mineral).
It took more than 70 years for the practical uses of vermiculite to be exploited on a commercial level. By 1915, it was being mined in Colorado and in 1923 the first large-scale vermiculite mine was started by the Zonolite Company in Montana.
These days, the mineral is being mined in South Africa, the United States, China, Russia, Brazil, Japan, Zimbabwe, and here in Australia. It is harnessed using open mining techniques where ore is detached from the other minerals and is then screened and separated.
Vermiculite Doors With FSE Special Purpose Doors
FSE Special Purpose Doors is a certified and experienced manufacturer of vermiculite fire doors. Our E-Core® fire doors consist of a single-piece internal core that has been constructed of vermiculite is that is reinforced with steel plates and can be used in conjunction with a diverse range of door edges and facing materials.
You can read more about E-Core® vermiculite fire doors here.