Impact on the metal envelope

The Building Regulations refer to any ‘building work’. This definition extends beyond new-build to alterations and extensions and any work which affects installations covered by the regulations, such as the installation of extra insulation or drainage systems. In any case where it is not clear whether the proposed work should be covered by regulations or not, the local buildings inspector should be consulted.

Building Regulations define the minimum fire safety requirements in terms of resistance and reaction to fire, depending on the building type and location (e.g. highrise).All Corus Colorcoat® products achieve a ‘class 0’ rating in England and Wales and equivalent in other regions. Systems using these products are available for almost all constructions.

Building Regulations set standards for the passage of sound through separating wall and floor constructions and therefore have very little impact on the design of the envelope. The regulations make specific reference to guidance in the design of schools, although again these are not prescriptive with respect to the building envelope.

Building Regulations in England and Wales cover the minimisation of condensation build-up in roof-spaces. The majority of pre-finished steel roofs fall into the category of low-pitch roofs or those where the ceiling follows the pitch of the roof. Where there is a gap between insulation and the external sheet, ventilation is required to ensure condensation does not make the insulation wet.

Building Regulations provide guidance on the designcapacity for rainwater drainage systems (gutters and down-pipes).

Building Regulations cover building fabric heat loss, air infiltration, heating systems, hot water systems, mechanical ventilation, air-conditioning and lighting in an attempt to reduce energy usage in buildings. For the design of the building envelope, regulations on fabric heat loss and air infiltration are important.

The levels of insulation required are different in the three legislative regions of the UK and Ireland, and in all cases some trade-off of energy usage is allowed between building components.