Japan Sustainable Building Database

Double skin

From the exterior inwards, the double skin consists of outer glass → air layer → roll screen → air layer → inner glass. On summer afternoons, when sunlight shines in directly, the sun’s rays are blocked and absorbed by the roll screen. Cooler load can be reduced by discharging the heat from the sunlight shining into the gallery through electric-powered natural ventilators installed above and below. Besides this, the double skin has the multiple function of natural ventilation and natural smoke discharge in spring and autumn. In summer, natural ventilation inside the double skin occurs an average of around 23 times / hour, and our measurements confirm that sunlight load can be reduced by 100 W/m² of the gallery floor area.