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Guidelines for Integrated territorial Planning:
Passive solar

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: they are more adaptable in historical contexts. 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, in the case of new constructions in historical contexts, come from some factors: cultural aspects, the regulatory framework and the relationship with the historical architectural heritage. Some passive solar systems could have architectural integration difficulties with the historical architectural heritage because of their aesthetical characteristics (for example, the particular colour of some devices in the indirect gain systems or the formal characteristics of the shading systems, used to prevent summer sun entering the interior). 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. In the case of new constructions in historical context, the regulatory framework doesn’t consider the architectural integration aspects.

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.

Case studies

Download PDF (Italian language)