Advanced windows are windows that use a combination of double or triple glazings, low-emissivity coatings, argon or krypton gas fill, and transparent insulation. Selecting advanced windows and orienting most of them to face towards the equator can significantly reduce the annual heating load. Studies have shown that houses designed using such passive solar concepts can require less than half the heating energy of the same house using conventional windows with random window orientation. Proper design and selection of shading devices can also result in reduced cooling loads.
A significant challenge for the next generation of modern dwellings is the integration of advanced window technologies, superior day lighting and passive solar heating for buildings in cold climates. New technology developments, in particular with advanced windows and airtight envelopes, make many older passive solar "rules-of-thumb" obsolete, and require the use of energy performance analysis tools.