Selectaglaze secondary glazing significantly improves the thermal performance of existing windows. Through the use of high performance seals and close fitted units; draughts are eliminated and heat loss is dramatically reduced. Secondary glazing is ideal for use in Listed and heritage buildings, as it is a reversible adaptation. Systems in the range also provide outstanding noise insulation and enhanced security. Units are independently performance tested – results can be downloaded from the website. Established in 1966 and Royal Warrant Holder since 2004, Selectaglaze provides a free technical advisory service and RIBA approved CPDs.