Glossary of Terms – Metal Roofing & Cladding

Metal Roofing – Metal roofing systems can be used on roof pitches greater than 5º, there are some systems that are designed to be laid down to 1.5º.  The British Standard for the design of metal roofing and cladding roofs is BS 5427 -1:1996 Code of practice for the use of profiled sheet for roof and wall cladding on buildings. There are two main forms of construction:
Twin Skin -This type of construction consists generally of a shallow profiled metal liner, a spacer system and an outer sheet usually in a deeper profile. The insulation is typically a mineral fibre quilt.


Composite Panels -These panels combine a liner, rigid insulation and weather sheet in a single factory made component.  Polyurethane or polyisocyanurate  are used for the majority of composite roof panels. Rigid mineral wool insulations panels can be used on walls.

Profiled Sheets – These are normally trapezoidal in shape, 30mm -40mm deep. Sinusoidal and half round profiles are available for wall constructions

Standing Seams – Standing seam systems use special profiles for the weather sheet with virtually no exposed through fasteners. Many of these systems can be laid down to 1.5º pitch.  Most systems are twin skin, but a composite panel version is available in the market place.

Fully Supported – These systems are as suggested fully supported on a a deck. Traditional copper, and lead zinc roofing fall into this category. Other materials include zinc, aluminium and stainless steel.  Many of the systems available are also known as longstrip roofing.