SW/ST

1. Stonewool Soffit can be fixed directly to the concrete slab, to provide an even surface. The rigid product is convenient to handle and allows for fast and easy fixing.

2. Using Stonewool Soffit on soffit areas, whether new build or refurbishment situations, provides the most efficient fire performance. The product achieves a thermal conductivity of 0.036 W/mK and has a Euroclass A1 fire classification.

3. Where applicable, ensure cavity wall insulation has continued past the soffit insulation to reduce Thermal Bridging.

4. Install Stonewool Soffit onto the substrate ensuring all joints are supported. The boards should be tightly butt jointed, laid staggered in a break bonded pattern and fitted tightly at edges and around any service penetrations. Any gaps or service penetrations should be addressed with propriety fillers and components in accordance with fire engineer specifications.

5. Fix Stonewool Soffit to substrate with approved fixings*, ensuring the fixings penetrate the substrate by a minimum of 40mm. Generally, 6 fixings (min shank diameter of 5.2mm) per board are required. Fixings should have a head diameter of at least 50mm. Distribute fixings evenly across the board, at a maximum of 300mm across and 400mm along. It is recommended to seek advice from the fixing manufacturer for specific guidance

6. For advice on soffit fixings, contact the system specifier, ensuring all fixings are accounted for when modelling thermal performance

7. Suitable Board Fixing ManufacturersHilti/EJOT/Fischer

*Fixing type and specification should be verified by the fixing manufacturers design, to take account of topographical and fire considerations. Account should be taken of any Thermal Bridging through the fixings as should the effect of any supporting beams. Fixing manufacturers: Ejot or Fischer