Insulation for Fire
ARC Cavity Stop Socks
ARC Cavity Stop Socks have been developed as thermal and acoustic fire stops that are designed to restrict the spread of smoke and flames within external masonry and timber frame walls, and further to minimise the effect of flanking noise pollution at wall junctions.
ARC Cavity Stop Socks are lengths of low resin, non-combustible, Rockfibre mineral wool, sleeved in 50 micron polythene for on-site weather protection.
- Four hours fire integrity - Warrington Fire Research test
- Polythene encapsulated cavity stop sock
- Easily installed both horizontally and vertically with compression fit
- Prevents the spread of smoke and flames within external masonry and timber frame walls
- Minimises flanking noise at wall junctions
- Available in standard widths of 65, 90, 100mm, and special cavity widths available on request
- TCB (flanged stopsock) also available for timber frame applications
Standard Dimensions
Dimensions – Mineral Wool |
Polythene Sleeves |
Pack Size |
|---|---|---|
65mm x 65mm x 1200mm |
50 Micron |
40 per pack |
90mm x 75mm x 1200mm |
50 Micron |
35 per pack |
120mm x 100mm x 1200mm |
50 Micron |
20 per pack |
Non standard sizes available on request.
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ARC Rockfibre Insulated Acoustic DPCs
ARC Rockfibre Insulated Acoustic DPCs has been specifically designed to provide fire protection and an acoustic barrier within the cavities of external walls.
ARC Vertical Fire and Acoustic DPC
The ARC Vertical Acoustic DPC enables the closing of an external cavity at the junction with a party wall, providing resistance to the spread of flame along the cavity. Where a separating party wall meets the external cavity wall, building regulations require the use of a mineral wool closer for acoustic insulation purposes. This product meets the requirement by significantly reducing the sound transmission along the cavity. The Rockfibre insulation is protected by a damp proof course on the external face, therefore satisfying a requirement of the National House Building Council (NHBC).
In order to seal off internal and external corners, an L-shaped acoustic DPC is available, as shown to the right, and is recommended by the Robust details (Jan 05). Dimensions available on request.
- Four hours fire integrity - Warrington Fire Research test
- Meets NHBC acoustic standards
- Part E compliant
- Robust Detail requirement
- Minimises transmission of flanking noise along the cavity of external walls
- Easily installed as brickwork is constructed
- Vertical and Horizontal applications
- Available in standard cavity widths of 50, 65, 75, 90, 100mm, and special widths available on request
Standard Dimensions
Suitable for Cavity Widths |
Dimensions |
Pack Quantities |
Fire Integrity |
50mm |
50mm x 260mm x 1200mm |
10 |
4 hours |
75mm |
75mm x 260mm x 1200mm |
8 |
4 hours |
100mm |
100mm x 260mm x 1200mm |
6 |
4 hours |
ARC Horizontal Rockfibre Fire and Acoustic DPC
The ARC Horizontal Rockfibre DPC has been developed to restrict the passage of smoke and flames and to minimize sound transmissions through external cavities at separating floor levels which is a requirement of building regulations. This product meets the requirement by significantly reducing the sound transmission along the cavity. The Rockfibre insulation is protected by a damp proof course on the external face, thus satisfying a requirement of the National House Building Council (NHBC).
- Four hours fire integrity - Warrington Fire Research test
- Meets NHBC Acoustic standards
- Part E compliant
- Robust Detail requirement
- Minimises transmission of flanking noise along the cavity of external walls
- Easily installed as brickwork is constructed
- Vertical and Horizontal applications
- Available in standard cavity widths of 50, 65, 75, 90, 100mm. Special widths available on request
Standard Dimensions
Suitabe for Cavity Widths |
Dimensions |
Pack Quantities |
Fire Integrity |
50mm |
50mm x 260mm x 1200mm (600mm wide DPC) |
10 |
4 hours |
75mm |
75mm x 260mm x 1200mm (600mm wide DPC) |
8 |
4 hours |
100mm |
100mm x 260mm x 1200mm (600mm wide DPC) |
6 |
4 hours |
Non standard sizes available on request.
ARC Fire Stops
The ARC Fire Stop prevents the passage of smoke and flames through narrow voids in buildings. Manufactured from high density Rockwool mineral wool, it is held in position by compression.
- High density mineral wool fire stop strip for closing off narrow voids
- Fire performance is outlined in Rockwool's Rigid and Semi-Rigid Slab data sheet
- 1200 long lengths
- Thicknesses available 10 – 100mm. Different widths and thicknesses available on request
Applications
- Top of masonry wall under soffit
- Above partitions
- Expansion joint in masonry wall
- Within metal cladding systems
- Between ceilings and walls
ARC Rockfibre Insulated DPC
The ARC Rockfibre Insulated DPC is an insulated DPC which has been developed to close masonry cavities for thermal, acoustic and fire applications. The primary reason for fitting the ARC Insulated DPC is to close off cavities around windows and doors preventing cold bridging. Can easily be installed as the brick and block work progresses where a traditional block return is used. Also available with a polyethylene insulation.
- 4 hours fire integrity - Warrington Fire Research test
- Easy to install
- Prevents cold bridging
- Exceeds the minimum requirement of 0.45 m² K/M provided the window is set back 30mm from the inner face of the outer brickwork
- Manufactured to NHBC standard
Insulation Dimensions |
DPC - Polyethylene |
Pack Size |
|---|---|---|
25mm x 100mm x 1200mm |
165mm width x 1300mm long. Black polyethylene to BS6515. |
20 |
25mm x 150mm x 1200mm |
225mm width x 1300mm long. Black polyethylene to BS6515 |
20 |
Non standard sizes available on request.
ARC Rockfibre Lamella Thermal and Acoustic Plasterboards
Designed to offer both thermal and acoustic insulation for internal walls, helping to improve upon statutory requirements. ARC Rockfibre Lamella Plasterboards are suitable for both refurbishment and new build projects in the domestic and commercial markets where increased thermal and acoustic performance is required. Rigid Rockfibre slabs are cut into strips and turned through 90 degrees so that the fibres lie at right angles to the plasterboard. This gives increased resistance to compression of a slab of the same density.
ARC Rockfibre Lamella Plasterboards are available incorporating tapered edge, square edge, and foil-faced plasterboards. Non-combustible to BS476: Part 4 1970 (1984) and Class 1 Surface Spread of Flame to BS476: Part 7 1987 and Class ‘0’ to the building regulations. The base Rockfibre material is chemically inert and compatible with all building materials, rot-proof and does not encourage the growth of fungi, mould or bacteria.
Also available with a standard rigid Rockfibre mineral wool slab insulation.
Various sizes and thicknesses available on request.
ARC Lamella Plasterboard Laminate:
Plasterboard length 2400mm x 1200mm wide x 12.5mm thick.
Plasterboard Conductivity 0.25 W/mk
Insulation: Lamella Rockwool Conductivity: 0.044 W/mk



