Light steel framed walls and floors

6.10

6.10.17Panels, cladding and boards

Panels, cladding and boards shall be compatible with the steel frame, be of a suitable thickness for the intended use, and be adequately fixed and installed.

In external walls, a clear cavity should be provided between the sheathing and the cladding. The cavity should:

  • be drained
  • have cavity trays and weep holes installed where the cavity is not fully maintained, e.g. at cavity barriers
  • be kept clean, free of obstructions and capable of draining freely
  • have drainage at the base of the cladding system equivalent to 500mm2 /m run, e.g. for masonry, one open perpend every 1.5m
  • have drainage openings placed to prevent the ingress of rain.

Wall panels should be:

  • fixed in accordance with the design
  • securely fixed together and to floors.

Masonry cladding

Masonry cladding should:

  • not be supported by the light steel framed walls unless shown in the design
  • be tied to the light steel framed walls with flexible wall ties fixed through to the studs
  • be constructed in accordance with Chapter 6.1 ‘External masonry walls’
  • be provided with soft joints to allow for differential movement.

To allow for movement, a 1mm gap per metre of masonry should be provided at openings and soffits.

Lightweight cladding

Lightweight cladding should be supported by:

  • the light steel framed walls on battens, or
  • other suitable means.

Wallboards

Wallboards should be:

  • fixed in accordance with the design and the manufacturer’s recommendations
  • attached to light steel studs using self-drilling, self-tapping screws at a maximum of 300mm centres.

In addition to the general guidance for wallboards, plasterboard should:

  • be fire-rated where used to provide fire resistance
  • comply with BS 1230 and be in accordance with Chapter 9.2 ‘Wall and ceiling finishes’
  • be a minimum of 9.5mm for stud spacings up to 450mm
  • be a minimum of 12.5mm for stud spacing up to 600mm