A Case Study of Energy Consumption and Indoor Environment in a WoodConstructed Office Building

In this study, field measurements andinvestigations have been carried out tounderstand the energy consumption and indoorenvironment of a sustainable designed officebuilding. The office building is located in thenorth of Sendai City, northeast area of HonshuIsland, Japan. It was completed in June 2006and covers an area of 4090 m2. The building isconstructed in wood so as to reduce thegeneration of C02. In order to improve theindoor thennal environment while reducing theenergy consumption used in heating, the wholebuilding is well insulated: high performanceinsulators are fitted in the exterior walls (180mm thick) and on the roof (200 mm thick);windows are fourfold-glazing with highinsulated sash. Besides, sunshade technology iswell utilized in this building to reduce theenergy consumed by cooling. For the HVACsystem, high quality air-conditioners with COPvalue over 5.0 are installed for heating andcooling, while mechanical ventilation system isused for ventilating. Measurements whichincluded indoor/outdoor air temperatures, insidewall temperatures and energy consumption fordifferent end-uses has been carried out sinceJune 2006.Measurement results indicated that indoor airtemperature was found much more stablecomparing to the outdoor temperature. It is dueto the use of the high performance insulatorsand well utilization of sunshade. Temperaturedifference between the height at 1.1 m and 0.1m was lower than 3 C which meets withASHRAE standard 55. On the other hand,energy consumption measured in this officeshowed much lower, referred to the statisticaldata, than other existing office buildings.