Wall type 1: solid walls of masonry

A. Solid wall, 200mm thick of bricks, blocks or slabs of clay, calcium silicate, concrete or cast stone.

Wall rendered or unrendered externally.

Insulation and plasterboard internally, with a cavity 25mm wide.

B. Solid wall as A. above.

Insulation applied to the external surface of the wall; protected externally either by cladding (of sheets, tiles or boarding) with permanent ventilation, or by rendering.

Wall with or without an internal surface finish of plaster or plasterboard.

Wall type 2: cavity walls of masonry

A. Cavity wall of 2 leaves of masonry separated by a 50mm cavity; each leaf, 100mm thick, of either bricks or blocks of clay, calcium silicate or concrete.

Wall rendered or unrendered externally.

Insulation applied as a lining to the internal surface of the wall and plasterboard.

B. Cavity wall as A. above.

Wall rendered or unrendered externally.

Insulation applied as a cavity fill.

Wall with or without an internal surface finish of plaster or plasterboard.

C. Cavity wall as A. above.

Wall rendered or unrendered externally.

Insulation applied to either leaf as a partial cavity fill so as to preserve a residual space of 50mm wide.

Wall with or without an internal surface finish of plaster or plasterboard.

Wall type 3: framed walls

A. Framed wall of timber standards and rails, with a vapour permeable sheathing to the framing covered with a breather membrane.

Masonry external cladding of 100mm thick clay brick or block, concrete or calcium silicate brick or block, dense in-situ concrete, lightweight concrete or autoclaved aerated concrete, with an externally ventilated cavity of 50mm but not more than 100mm wide between the cladding and the framing, the cavity ventilated to the outside by means of one open perpend joint for at least every 1.2 metre run at the top and bottom of the wall.

Masonry cladding rendered or unrendered externally.

Insulation applied as an infill to the framing.

The framing lined internally with a vapour control layer and plasterboard.

B. Framed wall of timber standards and rails with a breather membrane.

Cladding material, on battens and counter battens as required, of timber weatherboarding, tile or slate.

Insulation and internal lining as A. above.

C. Framed wall of timber or metal standards and rails.

Sheet or panel cladding material of fibre cement, plastic, metal, GRP or GRC.

Insulation applied either to the internal face of the framing with permanent ventilation behind any impervious cladding, or as an infill to the framing; in either case the wall lined internally with a vapour control layer and a lining.

Roof type 1: flat roofs [Note 1]

A. Flat roof structure of in-situ or precast concrete with or without a screed; with or without a ceiling or soffit.

External weatherproof covering; with insulation laid on a vapour control layer between the roof structure and the weatherproof covering. [Note 1]

B. Flat roof structure as A. above.

External protective covering; with low permeability insulation laid on a waterproof membrane between the roof structure and the external covering.

C. Flat roof structure of timber or metal framed construction with a board decking 19mm thick; with or without a ceiling or soffit.

External weatherproof covering, insulation and vapour control layer as A. above. [Note 1]

Note:

1. Roof types 1A. and 1C. are not suitable for sheet metal coverings that require joints to allow for thermal movement. See also ‘General’, f. of the provision deemed to satisfy G3.1.

D. Flat roof structure as C. above.

External protective covering, insulation and waterproof membrane as B. above.

E. Flat roof structure of timber or metal framed construction with a troughed metal decking; with or without a ceiling or soffit.

External weatherproof covering and insulation and vapour control layer as A. above. [Note 1]

F. Flat roof structure as E. above.

External protective covering, insulation and waterproof membrane as B. above.

Note:

1. Roof type 1E. is not suitable for sheet metal coverings that require joints to allow for thermal movement. See also ‘General’, f. of the provision deemed to satisfy G3.1.