Design for Solar Heating
Although reducing cooling
and electric lighting use are major concerns in Santa Monica, passive solar
heating can be an effective strategy in many types of buildings, especially
residential, hotels and others with low internal cooling loads. The high percentage
of clear skies during winter allows the use of sunlight to reduce or even eliminate
the need for supplemental heating.
Direct gain through south-facing
windows, clerestory windows and roof monitors is the most common method of passive
solar heating. These should have access to direct sunlight between 10 am and
2 pm from November to March and should be equipped with control devices to avoid
overheating at other times.
Where site conditions permit:
- Locate the building toward
the north and east parts of the site for greatest wall and roof exposure.
- Orient the building with
the long side east-west for highest winter gains and lowest summer gains.
Southeast or southwest orientation can capitalize on morning or afternoon
solar gains respectively without major losses in performance.
Carefully analyze the building
program to identify spaces and activities that benefit from passive solar heating.
Locate spaces that require heating where they have direct access to winter sun
and spaces that require cooling to face north or east.
Use a sunpath diagram and
shading masks, or simulation to assess potential shading on roof areas and vertical
southeast, south and southwest facing surfaces.
Cautions
- Constrained urban sites
make it more difficult to optimally locate buildings, and require greater
care in building envelope design.
- Locating building at
the northern edge of the site may require shaping/stepping the building to
minimize shading of neighboring properties.
- Building form and orientation
only establish the potential exposure to the sun. The area and location of
windows must also be carefully planned.
