Buffer zones

A free-running intermediate space between the interior and the exterior may reduce infiltration heat losses during winter, allow pre-heating of the supply air to the adjacent space and improve the effective U-value of the external envelope. Typical free-running spaces are entrance halls, conservatories or glazed balconies. The latter two should be located in the southern side and with advantageous window areas to allow indirect gain to adjacent spaces during winter. Shading devices prevent radiation from entering. Openings allow dissipation of heat during the hot periods.

3.3 Thermal mass

The thermal storage capacity of materials can be used to reduce the peaks of temperature in buildings. Temperature swings will also be reduced in strong inertia buildings.

During summer, thermal mass can be used to lower the upper daytime temperature, thereby reducing the need for cooling. The thermal mass is pre-cooled with night time ventilation, when outdoor temperatures are low, and allow heat dissipation the following day when indoor temperatures are high. Equally, in winter, thermal mass can absorb heat during the day for release into the space at night. This can potentially reduce heating demand. It will need a longer warming — up period, as the thermal mass has to warm up first. For this reason it is appropriate for buildings with permanent occupation and in particular with night occupancy. Offices and spaces that require a quick response to the environmental conditions may require a lower storage capacity.