It is possible to build an entire house, using wood only. None of the materials used in constructions offer such versatility. Wood is healthy: Wood does not attract dust. It acts as a regulator, absorbing and emitting the humidity in the space it exists. It provides heat insulation higher than its alternatives thanks to its cells filled with air, preventing heat transfer. Heat conductivitywood is typically as low as 0, 13 W/mK. The heating ratio of wood is fairly high. Thismeans that it requires much energy for increasing and reducing the temperature of awooden material. Wood needs as twice heat energy than stones and concretes.

Wood is economical. The life span of wood as a construction material, is commonly projected as 80 years, with a lot of wooden buildings dating from middle ages showing that this duration may well be past. The prejudice that wood needs frequent care is a reminiscent of those times that people thought it necessary to cover wood surfaces with impermeable films of paint.

Average life-span of the tree species commonly used in architecture is shown below:

Hardwood Species	In air			In freshwater
	In contact with soil	Isolated from soil
		In open air	Sheltered
Long-lasting wide Leaves Oak, Chesnut, Elm, Acacia, Hornbeam	8 -12 years	60 -120 years	+ 200 years	+ 500 years
Long-lasting conifers Black Pine Other Pines	8 -12 years	50 -100 years 40 – 90 yıl	+150 years	+ 500 years
Short Lasting Wide Leaves Ash, Beech Poplar, Tilia	+ 4-6 years – 4 years	+ 20 – 60 years + 30 years	+ 100 years + 50 years	+ 50 – 100 years – 50 years
Short Lasting Conifers Fır, Spruce	+ 4 years		+ 50 years	– 50 years

Source: Reha GUNAY Traditional timberworks and solutions 2002, İstanbul

Wood has unique technical properties. Materials expand with heat. Expansion causes decrease in strength of materials. Since steel is inorganic and non flammable, it is resistant to combustion. However, when it is used in buildings, it expands and collapses as a result of increase in temperature. Wood almost never expands with temperature. On the contrary, it dries and gains strength with the effect of heat.

Wood is safe: Water and carbon dioxide emerges when wood is burnt.

Wood is special: Each tree has its own naturally formed color, texture, grain and even scent. The structure of a wood changes according to the way it is cut. It is possible to find different wooden materials fitting different preferences of design and color. It can be painted and shaded to lighter or darker tones during use. All these make wooden products distinctive, individual and unique to the user. Wood windows and doors are fundamental components in interior decoration along with other architectural components such as flooring and furniture. Wood is a traditional building material for all cultures from East to West. Since its value is long engraved in human subconscience, it is a common source of warmness for people of all cultures. Because of the fact that wood is the material of both ancient and modern times, it is the ideal choice for a wide array of projects from renovations to avant-garde buildings.