Introduction

This report provides a review of how windows have been assessed in The Green Guide to Specification (fourth edition)^[1], including the application of the BRE Environmental Profiles methodology^[2], which underlies The Green Guide. The way that windows are addressed within building-level environmental assessment schemes such as the BRE Environmental Assessment Method (BREEAM; www.breeam.org) and the Code for Sustainable Homes^[3] is also explained.

The report aims to provide manufacturers and specifiers with a general understanding of the approach and decisions that have been made when applying the Environmental Profiles methodology to windows. The benefits and impacts of windows over their whole life cycle (cradle to grave) are discussed and opportunities for improvements within the sector are identified.

This report has been produced as part of a series on the production of The Green Guide to Specification. Many of the other reports in the series, eg Environmental impact of metals^[4] and Environmental impact of brick, stone and concrete^[5] may also be of value when considering the environmental impact of specific windows and their uses.