INBAR TNC Panel Based Bamboo Prefabricated House

Bamboo is a fast growing renewable resource. Compared to wood, bamboo has higher strength/weight ratio and can be a good substitute for wood. It has long been used as building materials for both structural and decorative uses, mainly in culm forms.

There is a big potential for bamboo based panels to be used as engineered building materials with good and stable strength and structural properties from a renewable resources. In addition, using bamboo in construction may not only contribute to a more sustainable construction industry and environment, but also benefit local farmers and economy.

In late 2004 INBAR and The Nature Conservancy (TNC) signed a MOU on Project "Promotion and Commercialization of Bamboo Building Materials" to enhance the use of bamboo as an alternative to building/structural materials such as wood and steel by business demonstrations.

In July 2005,INBAR singed a MOU with CAF, Fustar Co., and Beijing Chengdong Co. on the construction of a demonstration pack-flat bamboo panel prefabricated module houses and the house was completed in late Oct 2005

The major process for making bamboo plywood panel includes:

• Cross cutting bamboo culms to the desired length
• Cutting into long pieces and scraping nodes and removing both outer surface and inner surface and converting into slivers of 0.5~0.8 mm thickness and 20~30 mm width;
• Weaving slivers into curtains/mats;
• Air drying curtains/mats to 10~12% moisture content (m.c.);
• Dipping into 37% PF glue at a rate about 200 g/m2
• Drying the glued curtains/mats to 10-15% m.c;
• Assembling the curtains crossed with the adjacent layers, and the whole assembly is faced with one mat each at the top and bottom.
• Hot pressing at 130C140 1, for 1.5~2 min/mm, under 3-3.5 MPa.
• Trimming.
  The final dimension of bamboo plywood panel is 122 cm¡Á244 cm¡Á 0.9cm

The process of Assembling bamboo panel components includes:

The wooden frame (122¡Á244X 2.7cm) is prepared through sawing/planning/cutting into sizes/nailing;

Assembling two bamboo plywood panels with one wooden frame as a core by gluing and nailing.

Surfacing a gypsum board (122¡Á244¡Á0.9cm )by gluing and nailing.

The final dimension of the bamboo panel component is 122¡Á244¡Á5 cm.

Testing of properties of bamboo panel components

According to relevant Chinese National standards, the following properties are tested at the National Center for Quality Supervision and Test of Building Engineering

• Sound insulation
• Thermal transmission
• Fire-resistance

Testing of Sound Insulation

• Chinese National Standard GBJ75-84"Code for measurement of building sound insulation" is used.
• The size of the testing sample of panel component is 2.44m¡Á4m¡Á5cm, composed with one wooden frame in same size and 4 pieces of bamboo based wall panels of 2.44m¡Á1m.
• The testing result of sound insulation of the panel component is 32db

Testing of Thermal Transmission

• Chinese National Standard GB/T 13475-92 "Building element-Determination of steady-state thermal transmission properties-Calibrated and guarded hot box" is used.
• The sample size of panel component is 1m¡Á1m.
• Testing results: thermal resistance 0.29m2.K/W, thermal transmission coefficient 2.3W/m2.K.

Testing of Fire Resistance

• Chinese National Standard GB/T9978-1999 "Fire-resistance tests- Elements of building construction" is used.
• Composed with three pieces of panel components of 2.50m¡Á1.1m, the size of the testing sample of panel component is 2.5m¡Á3.3m¡Á5cm.
• The Fire-resistance limit tested is 20 min.

Workshop

Under this project, it was decided to organize a workshop in Beijing from Nov 24-26 in order to -

• explore potential of use of bamboo panels as a valuable construction material both for developing and developed construction markets
• demonstrate a module house from bamboo-based panels primarily for the relief from the global emergency situations and other urgent uses & identify R & D needs for future improvement
• develop partnership and draft a program focus on the pack-flat bamboo panel module housing