Windows, doors, and skylights, otherwise known as products of the fenestration industry, can gain and lose heat in the following ways:

– Direct conduction through the glass or glazing, frame, and/or door

– The radiation of heat into a house (typically from the sun) and out of a house from room-temperature objects, such as people, furniture, and interior walls

– Air leakage through and around them.

ISO 18292:2011, Energy performance of fenestration systems for residential buildings – Calculation procedure, gives the fenestration industry and its clients a reliable way to assess the energy performance of their products before they go onto the market for consumer use.

The standard provides a simple, clear, accurate and transparent procedure that calculates the energy performance of windows, doors and skylights, including the effects of frame, sash, glazing and shading components. It is designed to accommodate all climatic conditions – both internal and external – and relevant building characteristics and installation details.

Thor Endre Lexow, Secretary of the subcommittee that developed the new standard, comments: “A good building envelope is essential when designing sustainable and energy-efficient residential buildings. Windows make up a large part of the facades and they play an important part of the total energy performance of the building. By selecting windows with high energy performance the consumers’ energy bill will be lowered and the indoor thermal environment may improve.

The good news is that ISO 18292 will help the fenestration industry determine energy properties and compare products using national climate data and nationally selected reference buildings, thereby saving energy and money for all.”

ISO 18292 is intended to be useful to the following people: manufacturers to compare products and to show the energy benefits of new designs or technology; building officials and others involved in code development and enforcement to determine if products meet local codes, and by homeowners to compare different products and make informed product choices.”

ISO 18292:2011, Energy performance of fenestration systems for residential buildings – Calculation procedure, was prepared by ISO technical committee ISO/TC 163, Thermal performance and energy use in the built environment, subcommittee SC 2, Calculation methods. It costs 130 Swiss francs and is available from ISO national member institutes (see the complete list with contact details) and from ISO Central Secretariat through the ISO Store or by contacting the Marketing & Communication department (see right-hand column).