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Intumescent coated slabs

Product 4


Fibrous intumescent slabs that can be cut to allow services to pass through

£0.00 ex. Vat


Rock Fibre Slabs

High-density Rockwool slabs with an intumescent coating on both main faces. They are suitable for use as a permanent fire barrier in non-load bearing walls, floors and ceilings, as well as around services.

Supplied with intumescent jointing compound which is ideal for use over door frames between the door edge and ceiling. Additionally, its pliable material makes it easy to cut or resize with a sharp blade to suit any void. It’s possible to paint or also decorate over slabs without impairing its fire protective properties.

Supplied in 60mm thickness to provide effective support and fire protection, making them suitable to fill large wall openings. Using thicker slabs in larger gaps seals off voids and spaces more effectively. Also suitable for floors, however for large floor openings, it is recommended to add additional support using chicken wire mesh to reinforce strength and durability.

  • Intumescent slabs provide up to 4 hours fire rating depending on thickness and also requirements.
  • Can be used for large openings in floors, walls and ceilings
  • Effective acoustic protection

Where services and PVC pipes pass through walls or ceilings, Firoblok or intumescent wraps can be used for extra fire protection.

Fire barriers provide an effective solution for gaps or voids within buildings that require fire protection. Browse our full range of fire barrier products.


– Due to its high density, it can be used for large openings in floors, walls and ceilings

– Offers effective acoustic protection by impeding sound transfer through the centre of the structure and across its surface

– Ideal for use under raised flooring as a firebreak, providing 1-4 hours fire protection

Application Instructions

Where the slab is in a wall situation, just cut the slab to fit into the opening adhering
with the adhesive supplied, ensuring that Envirograf Wraps are fitted around any
PVC, copper or steel pipes and PVC electrical trunking.
For steel electrical trunking fit pads inside where passing through the slab. For cable
trays, then use Envirograf Product 29 cable tray pillows.
For floor openings 1m² without support. For hole sizes over 1m², firstly fit chicken
wire 1½” diameter, support around the perimeter with Envirograf FB/C1 Metal
Supports and wire mesh to services passing through the opening. For large openings
Product 4, ref: SUP Metal Supports can be used.
Then around any plastic, steel or copper the fit product 7, around electrical trunking
or steel trunking, fit Envirograf Pads and Cable Tray Pillows over cable trays or fit
Product 1 Envirograf Pillows around cables that are having to be regularly changed.
IS60 slab – this is a slightly smaller slab in size but very high density. Ideally suited to
large openings or complete walls, where ladders may need to be leant against or
areas where the filled area needs to be extra strong. Again, all services passing
through the slab must have Wraps, etc., around the pipes and services.
The coated slab is ideal for under computer room raised floors as a firebreak.

Case Studies

  • Priceless protection at Thornham Parva Church

    Protecting the unique oak retable at Saint Mary’s Church.

Order References / Sizes

REF        THICKNESS         COATING              SLAB SIZES                                PROTECTION                                              

IS40       40mm                   Double-sided        1200mm x 600mm                             2 hours

IS060     60mm                   Double-sided       1200mm x 600mm                             4 hours


SUP        Metal Support Batten for large floor openings (per metre)                                                                                       4-order-ref