Environmental Engineering Reference
In-Depth Information
buildings related to shadings, winds and local temperatures). An extended area
of built environment can, indeed, generate an increase of local temperatures
(urban heat island effect). In this aim it is advisable to maximize the open spaces.
2. For new buildings and for those subjected to demolition and total recon-
struction it is strongly suggested to create an open space with a surface of at
least 20 % of the design area creating shades by suitably planting trees. The
phenomenon is also limited by green roofs or employing reflecting materials for
roofs. Also the insertion of walking routes favouring the natural ventilation
giving rise to cooling of external walls of the buildings. It is also suggested, to
improve the microclimate around the buildings, the use of cool surface mate-
rials for external floor surfaces, among which: grass fields, reinforced grass
paving system, bricks, clear stones, cobblestones, such as also around the built
land, especially on the surfaces exposed to summer solar radiation from 12 a.m.
to 4 p.m. (standard time). The latter measure, using higher reflectivity materials
for such external surfaces, mitigates summer temperature peaks with a reduced
absorption of the solar radiation in the infrared spectrum.
These indications refer to the bio-climatic architecture, defining design criteria
for the control of external microclimate control close to the building.
The above measures produce a natural cooling effect during summer. The
plantings will be located also to protect the walls from winds during winter and the
direct solar radiation during summer.
They will be chosen so as to direct the summer winds towards the building and
to favour the natural ventilation inside the buildings (such notations are specified
in article 4 of the proposed guidelines). As it can be noted, the above rules are in
italics to indicate that they do not include any mandatory clause deriving from the
current national legislative framework. Therefore the local administrations can
decide whether such rules are to be set as ''voluntary'' or ''mandatory'' within the
annex to the new municipal building code. The Administration can also devise
some incentive measure to support the implementation of voluntary rules.
Illustrative example of contents of the articles within Area 2. Energy per-
formance of building envelope.
Art. 9 Thermal insulation of buildings (building features of the envelope—
winter)
1. For all classes of buildings if newly built or strongly restructured or under
extraordinary maintenance of the coating
18
(as an illustrative example, the
18
The interventions are described in article 3, paragraph 2, letters (a), (b) and (c) number (1) of
the Italian Legislative Decree n. 192/05 and modifications: (a) number (1) integral restructuring
of the building elements constituting the coating of existing buildings with floor area larger than
1,000 m
2
; (a) number (2) demolition and reconstruction in extraordinary maintenance of existing
buildings with floor area larger than 1,000 m
2
; (b) volume increase (gross heated) larger than
20 % of the entire existing building (the application is only related to volume increase); (c),
number (1), interventions on existing buildongs such as total or partial restructurings and extr-
aordinary maintenance of the building coating and volumetric increase out of what already
considered in letters (a) and (b) (only for the part of coating or of volume object of the interv-
ention) [Update of the Italian Legislative Decree n. 311/06].
