Experimental study on thermal performance of lightweight frame bamboo and wood walls

To study the thermal insulation performance of lightweight bamboo walls and promote the application of bamboo as a new material in energy saving construction, four lightweight frame walls representing one wood-based wall, one bamboo-wood-based wall and two full bamboo-based walls were studied by using guard hot box testing apparatus to obtain the thermal resistance and thermal transmittance. The thermal transmittance of the lightweight bamboo wall, the lightweight wood wall and lightweight bamboo-wood composite wall were compared with the experimental results including those in literature. The ISO 6946:2007 and finite element methods were used to analyze the thermal insulation performance of the lightweight walls and the reliability of the finite element simulation method was verified. The influences of anisotropic thermal conductivity, framing factor, framing thickness and nail spacing on thermal performance of lightweight bamboo wall were numerically simulated by finite element model. The results show that the thermal transmittance of lightweight steel wall is the largest, while the thermal insulation performance of lightweight frame bamboo and wood walls are similar allowing for the feasible substitution of wood by bamboo in construction. In particular, the thermal conductivity of frame material on laminated direction has certain effect on thermal insulation performance of lightweight bamboo wall as expected. Enlarging the spacing of the frame studs decreases the thermal transmittance, whereas increasing the framing thickness can greatly reduce the thermal transmittance. The thermal insulation performance of lightweight frame bamboo and wood walls are slightly affected by nail spacing and their effect can be ignored when the nail spacing is more than 150 mm.