Lafarge Plasterboard offer steel-framed external structural walls for use in constructions such as car parks, factories and workshops. If these walls are erected in close proximity to property boundaries, additional exterior fire protection is often required.
MultiShield or FireShield fire protection from Lafarge can be installed with external structural walls, defending fire from the outside for up to two hours. Both products are coated with a moisture barrier of breathable foil and are protected against the weather by external cladding.
In order for these external structural walls to be effectively protected, it is important to ensure that installation instructions are followed carefully. All control joints should be placed at maximum 12m intervals and any gaps between the top of the wall and the roof lining should be lined with fire resisting mineral wool to maintain the fire rating of the system. Fire mastic should be inserted into all gaps and around the wall perimeter and the plasterboard should be protected from water pooling on the ground.
Other specifications that should be met include:
- Plumbing and electrical services must be secured behind the face of the stud
- Laminating screws should be used to fix butt joints on the third layer
- Construction techniques that channel condensation and rain away from plasterboard should be utilised
- Plasterboard should not be fixed to steel more than 2mm BMT