Very High Temperature, Heat & Flame Resistant Tadpole Gasket


Vermiculite plays a key role as the main ingredient in fire-proofing and has been into use for many decades around the world, now very much mandatory for most of the commercial projects in INDIA apart from oil and gas projects.


Among the better known uses of vermiculite for fire-protection has been in fire-proof plasters. Basically “plaster” has been made from a mix of gypsum plaster and sand; and sometimes to strengthen the plaster reinforcing
materials like horsehair was added. The problem with sand plaster is that in case of fire the sand “explodes” and cracks, and can be easily destroyed.

In contrast, vermiculite plaster can turn a product which will be lightweight and fire-proof too.  For many decades, these plasters were used primarily in large refineries(Oil & Gas), large urban constructions where the combined benefits of weight reduction and fire-proofing were required. They were especially used to fire-proof steel beams, columns, and floors.

In the U.L. (Underwriters Laboratory) Fire Resistance Directory , for instance , there are  many  ratings of up to four hours for basic mixes of gypsum plaster and either perlite or vermiculite for use around steel beams and columns, or under metal decks. Here is a sampling of these:

In the U.L. (Underwriters Laboratory) Fire Resistance Directory, for instance, there are many ratings of up to four hours for basic mixes of gypsum plaster and either perlite or vermiculite for use around steel beams and columns, or under metal decks. Here is a sampling of these for Typical U.L. fire rated systems:

Structural columns Restrained and unrestrained assemblies Walls and Partitions
X401 — 2 HOURS A406 — 5 HOURS U-201 — 4 HOURS
X402 — 2, 3 & 4 HOURS A401 — 4 HOURS U-203 — 2 HOURS
X403 — 3 AND 4 HOURS A405 — 4 HOURS U-316 — 1 HOURS
X404 — 4 HOURS D403 — 4 HOURS U-409 — 1 HOURS
X405 — 4 HOURS D404 — 3 AND 4 HOURS U-413 — 2 HOURS
X406 — 4 HOURS D405 — 4 HOURS
X407 — 4 HOURS D407 — 2 HOURS
X408 — 4 HOURS D910 — 11/2, 2, AND 3 HOURS
X410 — 3 HOURS D911 — 2 HOURS
X411 — 3 HOURS P405 — 3 HOURS
X413 — 2 HOURS P406 — 3 HOURS
N.B.S./BMS-135 –2, 3 & 4 HOURS P909 — 1 HOURS

These ratings are for vermiculite and some for Perlite. Please check your U.L. Fire Resistance Directory for the most current values and for designs, listings of manufacturers, etc.

Since 1950’s and up to the present, many pre-blended forms of vermiculite fire-proof plasters have been sold under a number of different brand names—all with their own U.L. listings and benefits. Most of these are well known in the construction industry and among architects around the world and INDIA


Vermiculite has been important ingredient in most fire-proof door cores, and vaults, they have been used in fire-proof plasters because of the properties vermiculite posses light, inert, inorganic, and fire-proof.
The mix designs and formulas for these products obviously are proprietary, but the use of vermiculite is well known, and highly accepted all over the world.


Masonry walls (8,10, and 12 inches thick) can provide 2 hour fire rating easily. And by filling the cores with vermiculite, the ratings can be brought up to a 3-4hr rating. For instance, Underwriters’ Laboratory Design No. U905 shows that a 2-hour rated 8,10, or 12-inch concrete block wall is improved to 4 hours when cores are filled with vermiculite.
Vermiculite loose fill insulation has been tested in accordance with ASTM E-136 and was rated non-combustible.


Lightweight – Weighs approximately 60% less than many sand products, so with lightweight plasters, for instance, there is a saving of about one ton (1000 kgs) for every 100 yd2 (83.6 m2) of material applied ½ in. (13 mm) thick.

Insulating – 4 times more resistant to heat transmission than sand plasters. Permits savings in heating, air-conditioning costs and conserves energy.

Fire Retardant – Non-combustible and non-toxic, provides up to 5-hours of fire protection with minimum weight and thickness more than 50 fire tested designs by recognized laboratories.

Noise Reduction – Reduces sound transmission between partitions.

Adaptable – Packaged in (10/12.5/15) Kg bags depending upon the bulk density required. Easy to measure, mix and handle, Job mixing permits proper proportioning to meet different plaster based materials specifications.

Durable- As it is inert , cannot rot or decay. Strong but not brittle, endures freeze-thaw exposure. Successfully used on major construction projects in INDIA in IT buildings, commercial malls , Hotels, residential complexes and etc.

For more details, any queries write to Suggestions and information of suitable fire-proofing applicators will be provided based on the job and requirement of the project.