Design of buildings to exploit the characteristics and performance of the building fabric and the management of the building to achieve human comfort conditions without mechanical assistance.

Any disease-producing substance or (micro-) organism, eg a bacterium, virus or parasite.

A construction of posts, beams and battens and/or wires, generally attached to a building, to support creepers and/or shade-cloth to shade windows or an outdoor area.

The term “Permaculture” was coined (from permanent and agriculture) by the Australian ecologist Bill Mollison to describe an approach to the development of ecologically sustainable human settlements — including dwellings and agricultural and other production — which works with nature rather than against it, and emulates the complexity of natural eco-systems.

The use of energy from light to drive chemical reactions; the most common use of the term is to describe the use in plants of solar radiation to reduce carbon dioxide to carbohydrates coupled with the oxidation of water to free oxygen. This is the mechanism that converts the energy of solar radiation to chemical energy, which can then be used by animals (food) and people (eg food, fodder, firewood and petroleum). (See chlorophyll).

A photoelectric cell made from silicon which collects photons from solar radiation and acts as a source of electromagnetic force, and thus converts solar energy into useable electrical energy with a reasonable degree of efficiency (generally at low voltages). They can be used in conjunction with batteries to provide power 24-hours a day.

Silicon cells connected in arrays to provide electric current directly.

The effect that causes air to rise in a chimney or duct due to wind passing over the opening at the top of the chimney, thus reducing the pressure in the chimney.

Elements of a structure held in place and/or given flexural strength by a tension force added by means of tension steel (reinforcement) after construction, such as pre-fabricated concrete beams or slabs,  or terra cotta panels.

The moisture that falls on the earth’s surface from clouds; it may be in the form of rain, snow, hail and sleet.

A chart correlating the physical properties of air, such as wet- and dry-bulb temperatures, dew point, relative humidity and enthalpy.