TM37: Design for Improved Solar Shading Control

Avoiding overheating due to solar gain is a key design requirement to minimise the use of mechanical cooling and reduce energy consumption by cooling systems. Good low energy design will seek to minimise the effect of excessive solar gains in summer by appropriate orientation, massing and selection of the building façade. However, additional measures may still be required to provide solar shading to the building to reduce solar gains and theassociated risk of overheating.This publication provides guidance on the design of facades to incorporate appropriate levels of solar shading, and gives information on some of the design options available. The guidance in this CIBSE TM demonstrates how designers can address the issue of solar gain, ensuring that the building is able to benefit from solar gains when appropriate without suffering problems of excessive gains in summer.Under Part L of the 2006 Building Regulations for England and Wales, there is now an explicit requirement to limit heat gains to buildings. This will involve assessing designs of naturally ventilated buildings to ensure that they will not suffer from overheating in summer. This TM provides guidance on meeting the requirements, but will be of far wider relevance to CIBSE members. The physical laws which underlie the theory of solar heatingapply outside England and Wales, and so the guidance will be valuable to engineers seeking to address the issue wherever the sun may shine. The document also enables designers and facilities managers to quantify casual heat gains from lighting and other equipment in the building.The development of the TM was undertaken by Paul Littlefair of BRE, supported by colleagues at Faber Maunsell and BRE. The author also benefited from the input of the TM37 Steering Group, whose members were drawn from the industry, to try to ensure that the guidance is practical and relates to the systems available in practice. CIBSE is grateful to the members of the TM37 Steering Group and the companies which they represent fortheir contribution to the development of the guidance.This TM also represents one of the last CIBSE publications to be funded through the Department of Trade and Industry (DTI) Partners in Innovation scheme. This scheme supported a number of CIBSE publications from its inception in the mid-1990's until its recent closure. CIBSE acknowledges the support of DTI for this publication. CIBSE also acknowledges the support of the Office of the Deputy Prime Minister (ODPM) in those aspects of the TM relating to the application of the guidance in support of the requirements of the Building Regulation in England and Wales.