Civil Engineering Reference
In-Depth Information
Use of atria for climate tempering
Atria are intermediate spaces are typically glazed and not heated or cooled and thus have
a range of temperatures between those outside and those inside the climate-controlled
envelope.
With a passive behaviour that exploits direct solar gain in winter and allows for abun-
dant ventilation and shading in summer, these atria can effectively reduce thermal stress
on the proper envelope of the building and supply warm or cool air for natural ventilation.
Depending on the climate, these spaces may be closed or open. Moreover, atria can
play a social role as common spaces that can be used in inclement weather.
Example: new nursery school, Milan
The City of Milan commissioned a design
for a new childhood centre that would include advanced low-energy and climate-
conscious concepts. The design was developed in the framework of a research
funded by the Italian Ministry for University and Research about design strategies
and technologies for energy efficiency in mild climates.
The design revolved around the idea that it was possible “to heat the whole school
with a system sized for a single flat”. In the warm season, the building envelope
and especially the transparent elements had to be able to modulate the energy and
mass flow to avoid overheating (solar gain, shading, ventilation, etc.) and to pro-
vide comfort in free running mode whenever possible (Ferrari et al.
2006
).
Some of the innovative solutions include:
• thin-ilm photovoltaic system;
• natural ventilation by cross ventilation and stack effect (a solar chimney at
the top of the atrium roof);
• winter thermal comfort conditions are provided by a primary air venti-
lation system coupled with floor radiant panels. This combination mini-
mises electricity consumption in pumps and fans;
• a groundwater heat pump system supplies both hot water in winter for
space heating and DHW and chilled water for cooling during the warmest
parts of summer;
• life cycle assessment (Figs.
3.6
,
3.7
).
3.1.1.6 Control Systems
Mechanical systems have been designed in the past to supply cheaply available
energy to buildings with a very inefficient envelope; today instead, design is mov-
ing towards a closer integration of high performance building fabric and very
efficient mechanical systems (typically of smaller size compared to traditional
buildings). This approach exploits the passive performances of the building, leav-
ing to systems the role of refining indoor comfort conditions (thermal comfort,
air quality and lighting) through an efficient use of energy. Since the amount of
energy required to operate buildings will decrease significantly between 2010
and 2030 and energy prices are very likely to rise (International Energy Agency
cit.), it will be more and more important to manage buildings efficiently (e.g.,
avoiding waste and over-use of systems). One identified challenge, however, is
