The following guidelines come from a deep analysis of case studies, norms and regulations, in relation to the local level. This analysis is summarized in a card that can be downloaded in Italian language.
The passive solar systems are technologies aimed to
regulate the heat transfer between indoor and outdoor (with the main goal of
heat the lived room) exploiting the solar radiation and using parts of the
building as tools for its capture. The most common passive solar systems used
in the buildings are the glasshouse and the sun-facing wall (Trombe wall). The use of passive solar systems can provide thermal
comfort reducing the use of heating technological systems, which imply large
energy consumption from fossil fuels and pollutant emissions. The principles of passive solar planning can be
adapted more easily to the new constructions than to the renovation and refit
works of existing buildings. Moreover passive solar systems refer to the use of
flexible and non standardized devices. In particular, the direct gain systems
have a little visual impact thanks to their simple image and are easy to use. Architectural integration of passive solar systems with
a bioclimatic approach can be an opportunity to improve also the aesthetical
features of the building. Despite
that, the main difficulties with the architectural integration of passive solar
system come from cultural factors and the regulatory framework.
Cultural
problems are still strongly connected to an insufficient technical knowledge
about passive solar systems but some problem can come, later, from the
inability of the users that may don’t know how to use and to keep the system
working. The
problems that can come from the regulation are more difficult to solve
especially when is necessary to make new volumes (for example the sunrooms) on
buildings where is not allowed any increase.
Furthermore,
quantitative predictions on solar gain potential and microclimatic analysis are
still difficult. This is also due to the fact that passive solar systems depend
on the solar energy (which is not a constant source). Actually there are
several calculation tools but they are not user-friendly for designers. Besides
possible architectural integration difficulties can be related to the interior
habitable spaces. For example, in the case of direct gain systems or sunrooms,
it is not possible to cover thermal mass floors with carpets or fitted carpet
and the furniture layout must be kept as bare as functionally and aesthetically
possible. Finally,
even if the passive solar systems are simple, they need peculiar frames,
windows and valves for the air control that
commonly are difficult to find on the Ligurian and national trade. Moreover they are often unknown to the local labour.
The diffusion of the
passive solar system in new constructions, could be facilitated following some
advices such as:
Indication
for the Bio-construction Action Plan
Pursuant to the guidelines written above, here are synthetically reported the criteria/examples for pilot projects to be financed in MED territory, in relation with the specific treated theme. These criteria/examples, together with the ones resulting from all the themes of eco-construction tool matrix, will make up a Bio-construction Action Plan for each partner countries.
Possible
criteria for MED bio–housing quality certificate
The internationally recognized green building certifications, normally give few indications about the use of passive solar systems. The same happens for the most common Italian certification system, so called “Protocollo Itaca”, the Italian version of “Green Building Challenge” (made by a network of 25 countries). In “Protocollo Itaca” for residential buildings, for example, there is only a mention of these systems, in the sub-section 1.1.1 of the light version. It isn’t considered necessary that green building certifications as “Protocollo Itaca” should be made more complicated. However more space should be given to the use of passive solar systems both for new construction works and for requalification of recent buildings, especially because of the advantages that this systems give: energetic, aesthetical and functional.