65mm Rockwool PWCB Cavity Barrier products deliver superior fire protection specifically engineered for timber frame and masonry construction. These barriers exceed minimum building regulation standards for fire resistance in concealed wall cavities, with proven performance up to 60 minutes of integrity and insulation.
Manufactured from non-combustible stone wool and wrapped in protective polythene sleeves, these cavity wall insulation solutions provide thermal and weather protection throughout installation. Colour-coded sleeves—red for TCB and white for PWCB—enable quick product identification on site.
The Rockwool cavity barrier combines fire safety, acoustic flanking control, and thermal bypass prevention in one integrated product. It also seals perimeter edges effectively, minimising air infiltration and reducing associated heat loss.
The 65mm Rockwool PWCB Cavity Barrier performs effectively in both vertical and horizontal configurations. For vertical installations, secure both flanges to the inner leaf at 150mm intervals using staples or clout nails before the outer cavity wall compresses the product. In horizontal applications, fix only the top flange of the polythene sleeve.
Euroclass A1 fire rating: ROCKWOOL Cavity Barriers meet the highest fire safety standards and have been tested and assessed for up to 60 minutes of fire resistance (both integrity and insulation) in accordance with BS 476: Part 20.
65mm Rockwool PWCB Cavity Barrier has been engineered to surpass minimum Building Regulation requirements for fire resistance in concealed wall cavities, delivering enhanced safety performance.
These barriers remain unaffected by building movement, shrinkage, or thermal changes, maintaining consistent protective performance throughout the building's lifespan.
Designed for robust on-site handling, these barriers provide lifetime protection once installed, safeguarding your structure for decades to come.
ROCKWOOL Cavity Barriers deliver flexibility for both vertical and horizontal applications. Vertical installations allow both flanges to be secured to the inner leaf at 150mm intervals, whilst horizontal applications require only the top flange of the polythene sleeve to be fixed.
ROCKWOOL Cavity Barriers effectively suppress flanking noise transmission through concealed cavities in both external wall insulation and separating walls, enhancing acoustic comfort throughout the building.








