Envirograf WBS Cavity Barrier
  • Envirograf WBS Cavity Barrier

Envirograf VWBS Ventilated Cavity Barriers

Product 55

VWBS Ventilated Cavity Barriers made from flexible fireproof sponge, for use in brick/block cavities. Its unique spring properties mean it can be fixed simply by pressing into place.

  • Refer to sizes below
  • Must only be used horizontally
  • Barrier must be 10mm wider than the cavity
  • Offers thermal insulation
  • Up to 2 hours fire protection
VAT excluded

£29.00 Tax incl.




Ref Cavity Width Actual Width Sponge Thickness Rows of Ventilation Holes
VWBS80 80mm 90mm 40mm 1 Row of Holes
VWBS135 135mm 145mm 40mm 1 or 2 Rows of Holes
VWBS165 165mm 175mm 40mm 1 or 2 Rows of Holes
VWBS210 210mm 220mm 40mm 1 or 2 Rows of Holes
VWBS265 265mm 275mm 40mm 1 or 2 Rows of Holes

Both types of fire barrier are available to order in 1m and 2m lengths.

Envirograf VWBS Ventilated Cavity Barriers fix easily simply by pressing into place in brick/block cavities.

The ventilated VWBS version can only be used horizontally and has intumescent material that expands in a fire, sealing up the ventilation holes to prevent the spread of smoke and fire for up to 2 hours. This can delay the spread and contain a fire outbreak, giving extra time for evacuations and preventing more damage.

The fireproof sponge offers durability and moisture protection. Ensure that the sponge barrier is 10mm wider than the cavity.

The sponge cavity barriers are 40mm thick, and ventilation types are available for purchase with 1 or 2 rows of vent holes.

Examples of use

Many buildings are honeycombed with cavity walls and voids in walls, roofs and floors, especially high rise flats and apartments and offices. Fire and smoke can spread up through these cavities quickly, burning insulation and services, travelling to other parts of a building and wrecking more damage and endangering lives.

Envirograf Fire Cavity Barriers should be fitted by experienced professionals to ensure they are installed correctly. Products can only be guaranteed by Envirograf if fitted correctly and incorrect installations will be condemned if inspected. Check labels, fixing brackets, manufacturer installation instructions, etc. Should a site visit be required to check installation, this can be arranged upon request but will be chargeable.

IMPORTANT FIRE PRODUCTS NOTICE: The information displayed on this website should be used as a guide ONLY and our Technical Department should be contacted to obtain a tailored specification and any advice necessary before you place an order for fire protection products. Fire protection products are non-returnable except in accordance with Condition 8 of the Terms and ConditionsWe will not be held liable for any resulting damage to property, human life or monetary costs incurred due to the incorrect specification you have prepared or use of fire protection products caused by your negligence, including your failure to have contacted us to obtain the relevant advice/specification.

Any Envirograf products to be used in or for Harrods department store should be authorised with our Technical Team prior to purchase.

It is your responsibility to read the Product Data Sheets (available below) before you place an order and prior to application of the product. The content of this website is our best recommendation and is not advice. Coverage rates quoted are approximate, you agree that coverage depends on the condition of the substrate, surface absorption, texture and application method. We ALWAYS recommend a trial area is coated to ensure the product meets your requirements before use.

Product Details
Product 55

Customer agrees that before placing an Order, Customer has read and understood the most up to date Product Data Sheet for the Product. Where we have access to the Product Data Sheet from the manufacturer, we will either provide a copy on request, or include a link to the Product Data Sheet available on the manufacturer’s website. Customer further agrees that we have no liability for any errors or omissions contained within the Product Data Sheets. For more information, please see our Terms & Conditions of Sale.

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