Hybrid construction: wood frame storeys on concrete structure

Hybrid construction where wood construction is combined with concrete and/or steel construction is a promising opportunity for the future of China. This includes the construction of buildings which have the lower storey or storeys (or parkade) in concrete to which a light-weight energy-efficient wood super-structure can be attached.

In Europe, wood frame buildings of up to six or seven storeys are achieved using a concrete lower storey. And in China, buildings of up to three wood frame storeys on top of up to four concrete storeys may soon be accepted.

These hybrids are ideal for combining commercial space, such as stores and offices, in the concrete portion of the building, with housing in the wood frame part. In some settings, hybrids may be the most practical, efficient, and cost-effective option.

Hybrid construction: wood frame walls in concrete structures

Chinese fire safety codes allows the use of infill wood frame exterior walls in concrete structures up to six storeys and is likely soon extend it to seven storeys high for residential, offices, and certain factories and warehouses. These structures have been built cost-competitively at up to twenty storeys in northern Europe for a number of years, where increasingly stringent energy-efficiency requirements are a key driver.

Exterior infill walls are light, as they are designed to take only the load of their weight and the wind and seismic loads that directly affect them. They can be prefabricated in a factory or built on site and have very good insulation characteristics in relation to their thickness, providing substantially better energy performance than traditional concrete, masonry or steel construction.

Where wood frame is used for interior walls in concrete and steel structures as partitions, they provide flexibility of design, including floor layout, fire safety, sound insulation, and renovation. Wood infill partitions are non-structural, lightweight, and are suitable for a range of interior finishes. They can also be designed to meet the fire and sound requirements for apartment partition walls. Wood frame partitions are approved up to eighteen stories.

The main benefits of exterior wood infill walls:

  • Outstanding thermal properties and energy conservation
  • Reduced wall thickness maximizes usable living space by a typical 2 per cent
  • Shorter on-site construction time through pre-fabrication
  • Reduced foundation load
  • Improved seismic performance

Hybrid construction: wood frame roofs on concrete structures

Many of the typically concrete medium-rise residential buildings throughout China have flat roofs that tend to leak and are poorly insulated for energy conservation and thermal comfort. These existing roofs can with advantage be covered with a pitched wood frame truss roof. This is a cost-effective way of keeping the rain out, improving the look of the building, and reducing energy costs, with additional insulation in the roof cavity. It is also an effective way of delivering a thermally comfortable attic space for extra accommodation, or to install mechanical systems for heating, cooling, and ventilation.

This system is as competitive for installing roof systems on new concrete structures as for replacing old concrete roof systems.

Light-weight wood frame storeys on multi-storey concrete building, Europe
Light-weight wood frame storeys on multi-storey concrete building, Europe
Assembling pre-fabricated wood frame exterior infill wall panels in a multi-storey concrete structure building, Europe
Assembling pre-fabricated wood frame infill wall panels in a multi-storey concrete structure, Europe
Re-roofed apartment buildings with habitable attic, downtown Beijing
Re-roofed apartment buildings with habitable attic, downtown Beijing

European Wood (in China)
C412, Beijing Lufthansa Center
50 Liangmaqiao Road, Chaoyang District
Beijing, P.R. China 100125
T +86 10 6462 2066, F +86 10 6462 2067
Sino-European Wood Center
Room 202, Engineering Department,
Taoliyuan Hou, Xuhui Campus of Jiaotong University,
No.655 Panyu Road, Xu Hui District, Shanghai