Report # 82 : Single-family wood frame house

by Carlos E. Ventura, Mehdi H. K. Kharrazi

Single-family wood frame construction represents the most common housing construction practice found throughout Canada and constitutes over 50% of the housing stock in British Columbia. A typical Canadian-style modern wood frame house consists of a concrete foundation, upon which a platform is constructed of joists covered with plywood or oriented-strand board (OSB) to form the ground-floor level of the house. This platform is connected directly to the foundation with anchor bolts, or alternatively, supported by a short wall, a so-called “cripple wall,” “pony wall,” or “stub wall,” which should be connected to the foundation with anchor bolts. On this base, the exterior and interior walls are erected, which consist of a horizontal sill plate with vertical timber studs with board or panel sheathing nailed to the studs on the outside of the building. The roof structure typically consists of prefabricated trusses, which are covered with sheathing and roof tiles (Rainer and Karacabeyli 2000). Because this is generally considered to be a non-engineered construction, the Canadian National Building Code does not usually require direct professional architectural or engineering involvement. Specific seismic construction requirements and calculation/design requirements for seismic resistance are currently not included in Part 9 of the Code, which addresses low-rise residential wood frame construction. There is no evidence of substantial damage to this type of construction in past earthquakes in Canada, which have occurred away from densely populated urban centers. However, recent experimental research studies (Earthquake 99 Project at the University of British Columbia), focused on seismic performance of wood frame construction, have revealed vulnerability in this type of construction to seismic effects, depending on the age and wood construction technology.


Report # 65 : Wood frame single family house

by Christopher Arnold

Wood frame construction is typical for single family houses throughout the USA. Historically, in the East, Midwestern and South, brick masonry and stone were used for house construction, but this began to be superseded by wood frame around the turn of the 19th century. In the earthquake-prone western part of the US, wood frame has been dominant over stone and brick. The development of present-day wood frame construction began with the appearance of standardized sawn lumber and cheap machine-made nails. By 1840, the typical wood frame house was built of milled lumber in standard sizes. The standardized wood frame structure is now augmented by a wide range of compatible standardized components such as doors, windows, electrical and plumbing fixtures, and the like, that are designed to be easily installed in the wood structure. Because wood frame walls are hollow, alternative levels of insulation can be installed, enabling accommodation of any climatic conditions and easy installation of plumbing and electrical services within walls, in the open spaces above the ceilings, within the floor structure, and in the space between the first (ground) floor and the ground below. Because of their light weight (compared to brick or stone), their relatively large number of walls, and the use of a multiplicity of nails for connections, wood frame houses have traditionally performed well in earthquakes. Deaths and serious injuries are very rare in these structures. Today’s wood frame construction is highly codified and regulated, with a good standard of inspection by suburban local building departments in earthquake-prone regions. In smaller towns and rural areas quality control may be lacking.


Report # 57 : Wood panel wall buildings (typical seria 181-115-77 cm of “Giprolesprom”)

by Mark Klyachko, Andrey Benin, Janna Bogdanova

This is a rural housing construction practice widespread in the forested areas of Russia. Buildings of this type are common in seismically prone areas of Russia (Far East, Siberia, Baikal Lake Region). The load-bearing structure is made of wood panel walls. Buildings have timber roof and fieldstone or concrete strip foundations. Typical seria 181-115-77 cm of ‘Giprolesprom’ for seismic regions is an example of this building type. Seismic resistance is relatively high, provided that the quality of materials and the construction are satisfactory.


Report # 56 : Timber log building

by Mark Klyachko, Andrey Benin, Janna Bogdanova

This is a rural housing construction practice widespread in the forests of Russia. Buildings of this type are common for seismically prone areas of Russia (Far East, Siberia, Baikal Lake Region, North Caucasus). The load-bearing structure is made of wood. To construct the walls, timber logs are sawn horizontally in a square or circular cross section with special end joints (similar to dovetail joints). Buildings have timber roofs and fieldstone or concrete strip foundations. Typical seria 146-115-77 cm of ‘Giprolesprom’ for seismic regions is an example of this building type. Seismic performance of these buildings is good if the construction quality is adequate.


Report # 35 : Traditional wood frame construction (yurta)

by Ulugbek T. Begaliev, Svetlana Uranova

This type of building is the national traditional dwelling of the Kyrgyz people. It is a light portable construction. The bearing structure of a yurta is a special wood frame, consisting of wood poles. The wood frame is covered by felt tension cloth. The floors are traditionally covered with felt rugs (koshma). Yurtas can be easily disassembled and moved to new places. They are warm in winter and cool in the summer. The buildings have only one door and one opening in the roof. Yurtas are circular in plan. The diameter is usually 4 m#6 m. This type of building is used at the present time by shepherds, particularly during the summer, for celebrations and funerals, and as temporary buildings during extreme situations in Kyrgyzstan. The yurta is a very light structure, has a symmetrical plan, and has good seismic resistance.