What passive solar features should be considered in planning permits?

Planning for South-Facing Glazing

When planning a building with passive solar features, south-facing glazing is crucial. It allows sunlight to enter the building during winter months, warming the interior space. The ideal orientation for south-facing glazing is between 15 and 30 degrees east of true south to maximize winter sunlight while minimizing summer heat gain. A minimum of 10% of the total fenestration area should be south-facing glazing, which can account for 20-30% of the building’s total heating needs.

Incorporating Thermal Mass

Thermal mass is another essential passive solar feature that helps regulate indoor temperatures. Materials like concrete, brick, or stone are effective thermal masses, as they absorb and release heat slowly. A minimum of 1 square foot of thermal mass per square foot of south-facing glazing is recommended to effectively moderate indoor temperatures. This can be achieved through the use of thick walls, concrete floors, or even decorative elements like stone or brick.

Strategic Overhangs and Orientation

The strategic placement of overhangs and the building’s orientation on the site are critical components of a passive solar design. Overhangs should be designed to cast a shadow on the south-facing glazing during summer months, reducing heat gain and preventing overheating. Ideally, the building’s long axis should be aligned with the southern sun, and the roof should be oriented to maximize winter sunlight while minimizing summer heat gain. A site analysis can help determine the ideal orientation and overhang design for a specific location.