Passive solar building design utilizes direct sunlight and thermal mass to heat interior spaces without mechanical systems. Key elements include orienting the building on an east-west axis with south-facing glass, incorporating thermal mass floors and walls to absorb sunlight during the day and radiate heat at night, and using shading to prevent overheating in summer. Passive solar cooling strategies rely on natural ventilation through operable windows and ventilation chimneys or wings to draw cool air through the building without electricity. While initial costs may be similar to conventional buildings, passive solar reduces energy costs for lighting and heating over time in a sustainable way.

1. PASSIVE
SOLAR
BUILDING
Rohit Chaurasia
71/08

2. WHAT IS
PASSIVE SOLAR BUILDING?

3. PASSIVE SOLAR BUILDING RULES OF
THUMB
• The building should be elongated on an east-west axis.
• The building’s south face should receive sunlight
between the hours of 9:00 A.M. and 3:00 P.M. (sun
time) during the heating season.
• Interior spaces requiring the most light , heating and
cooling should be along the south face of the building.
Less used spaces should be located on the north.
• An open floor plan optimizes passive system operation.
• Use shading to prevent summer sun entering the
interior. Sustainable by design has an online calculator
for Sun Angles and from that you can figure the
overhang calculations.

4. SOLAR BUILDING

5. Direct heat gain in winter

6. PRIMARY ELEMENTS OF PASSIVE SOLAR
HEATING
DIRECT GAIN:
• SPACE IS USED AS SOLAR COLLECTOR AND
DISTRIBUTER
• SOUTHFACING GLASS
• THERMAL MASS FLOORS AND WALLS ARE THE
FUNCTIONAL PARTS
• IN DAY TIME THEY ABSORB SUNLIGHT AND
RADIATES IN NIGHT

7. INDIRECT GAIN
• Thermal mass located between sun and living space
THERMAL STORAGE WALL SYSTEM:
• Thermal mass located immediately behind the glass
ROOF POND SYSTEM:
• 6 to 12 inches of water layer
• Best for low humid areas but in high humid areas it can be
modified
INTERIOR WATER WALLS:
• Water has good convective properties
• Widely fluctuating temperature is not often a problem when
interior water walls are used as heat storage

8. Thermal Mass Wall or Trombe Wall
Day and Night Operation

9. ISOLATED GAIN
• This part is seperated from living areas
• Utilize 15 to 20 % of sun light
• Isolated gain is combination of direct and indirect
gain
• Heating is done by convection process though air

10. Sunroom function in summer

11. PASSIVE SOLAR COOLING
• uses in removing the unwanted heat from building
• Primary strategy for cooling building, without any mechanical
or electrical source
VENTILATION AND OPERABLE WINDOWS:
• Employ natural ventilation
• Place operable windows on the south exposure If a room can
have windows on only one side, use two widely spaced
windows instead of one window.
• Place operable windows on south exposure

12. Wing wall
• Panel placed along side the window
perpendicular to the wall
• Wing wall will accelerate natural wind speed
View of Wing Walls Airflow Pattern

13. Thermal chimney
• Uses to draw hot air out of building

14. OTHER VENTILATION STRATEGY
• Make the outlet openings slightly larger than
the inlet openings.
• Place the inlets at low to medium heights to
provide airflow at occupant levels in the room
SHADING:
• It is done in south direction

15. Thermal Chimney Effect Built into
Home

16. PASSIVE SOLAR WATER HEATING
• Heated water can be used for domestic
purpose
• It involves no pump or electrical device
• In swimming pools

17. COST AND ECONOMICS
• Same or slightly more than conventional
building

18. CONCLUSIONS
• Passive solar building is eco friendly as well as
it cost is almost same as conventional
building
• It is less costly in lighting purpose
• Beneficial for health
• So people should be encouraged for the use of
passive solar buildings.