Sunspaces and Greenhouses

A sunspace is a glazed room on the south face of a building that functions as a thermal buffer: it collects solar energy and raises its temperature significantly above ambient, and this warmer air or the radiant heat from the heated glazed structure reduces heating loads on the adjacent interior spaces. A sunspace that is designed to grow plants year-round is a greenhouse; one designed primarily for passive solar gain and human use is typically called a solarium or sunroom.

Sunspaces are particularly valuable in very cold climates where direct gain is insufficient to meet heating needs, and in climates where south glazing must be carefully managed to prevent summer overheating — the sunspace’s own temperature can be controlled through ventilation without affecting the main living space. They are also the primary food production zone in a Pangea building, combining passive solar heating performance with year-round growing capability. The north wall of the sunspace is typically the south-facing wall of the main building, which can be opened in winter to admit warm air and solar radiation, and closed at night to retain heat.