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Sealmaster Intumescent Plaster


Sealmaster Intumescent Plaster is a chemically modified surface coating and space filler. Small gaps, cracks, crevices and fissures often cause weakness in a building. If they occur where fire resistance is specified - in areas around fire doors or where service pipes and cables pass through a wall or floor, for example Sealmaster Intumescent Plaster should be used to make good the weakness. Under normal conditions, the plaster performs the conventional cosmetic and draughtproofing role of space filling compounds. Under intense heat, however, the plaster carbonises and its intumescent action swells to impede the passage of flame and smoke.

Intumescent Plaster provides a hard, durable fire resistant barrier between masonry construction and wooden frames. It can be used:

To fill over-large lock or latch recesses in wooden doors to prevent premature charring and failure in a fire;
To fill holes and gaps around ducts, pipes and cables where Sealmaster Intumescent Compound may not be applicable;
As a dry filler to plug holes drilled in wooden doors for cables etc. (for example: ventilator cables), and used wet to cap the hole.

Equal quantities of each of the two parts of the plaster should be mixed together thoroughly, and then water added and stirred to the desired consistency. The plaster should be applied like a conventional plaster with atrowel. When set, the plaster can be over painted.

This product is available ex-stock with delivery normally within 7 - 10 days. Express overnight delivery can be arranged on request.

technical information

Material: Chemically modified intumescent plaster supplied as a two part powder to mix with water. Setting: Sets hard overnight. Quantities: Supplied in two containers of equal weight, in two sizes: 800g and 4.75kg (combined content), to produce 500cc and 3500cc respectively. Colour: Cream. Flammability: This material does not burn. Fire Resistant Rating: Tested by TRADA to BS 476 for over 60 minutes. Durability: Resistant to atmospheric moisture. Non shrinking.

Health and Safety:
This product is not considered toxic. Repeated, prolonged contact of the plaster mix on sensitive skin may cause dermatitis, in which case rubber or PVC gloves should be worn when handling the product. Wash exposed skinsurfaces after use with warm soapy water. Minimise dust by opening and mixing in a well ventilated area, and avoid inhaling dust as this may cause choking. If affected go into fresh air until fully recovered. Ingestion and eye contact should be avoided. Any contamination of the eyes should be treated by irrigation with clean water as soon as possible. If swallowed, drink some water. In either case, if discomfort persists, seek medical attention. Normal standards of industrial hygiene should be observed when handling this product.

Disposal of Waste Material: No special provisions are necessary for the disposal of waste material. Storage: When storedcool and dry, this product has an indefinite shelf life.

Sealmaster provide initial design services with technical support at all stages of work from planning through to site installation, without obligation.

Sealmaster can take on the total package responsibility of supply and installation using in-house expertise or approved specialist sub-contractors.

further information
Our sales and technical teams will be only too pleased to provide further advice or technical information on Sealmaster's fire penetration systems or any form of passive fire protection.

  • Sealmaster Intumescent Plaster