The Ventilated Roof adopts advanced technology in the field of roof insulation and is mainly used in the construction of habitable attics. It is composed of a panel of insulating material made of closed-cell sintered expanded polystyrene (EPS). It is self-extinguishing, non-toxic, hygienic and does not deteriorate over time, shaped with protruding supports to create ventilation channels and is coupled with a sheet of multilayered wood with crossed flakes of long phenolic-type fibre (OSB/3). The OSB/3 sheet is pre-treated with anti-mold, anti-woodworm and water-repellent resins, is very resistant to compression, can be walked on during installation and is incompressible by the weight of the roofing materials normally used (terracotta tiles, concrete tiles, Canadian tiles, etc.). The special shaping of the insulation panel allows the creation of a ventilation chamber between the insulation and the phenolic wood which acts as a support for the roofing. The constant and consistent circulation of air that is created inside the panel removes the heat transmitted by the roof covering, protecting the underlying layers from overheating. This ventilation increases and strengthens the characteristics of the insulation by expelling heat from the ridge of the roof, thus obtaining a reduction in the temperature in the rooms below of 8-10°C. In addition to the risk assessment to be carried out "taking into account the external fire resistance class of roofs and roof coverings and the fire reaction class of the photovoltaic module", other assessments aimed at demonstrating the achievement of the objectives of the guide are admissible. If it is intended to take into account the external fire resistance class of roofs and roof coverings and the fire reaction class of the photovoltaic module (case 3/a of Annex B), the following combinations can be considered, in general, acceptable: •roofs classified as Froof and PV panel of class 1 or equivalent fire reaction; •roofs classified as Broof (T2, T3, T4) and PV panel of class 2 or equivalent fire reaction; •top covering layers (waterproofing and/or insulation packages) classified as Froof or F installed on EI 30 roofs and PV panel of class 2 or equivalent fire reaction. The classification of roofs and roof coverings must refer to the applicable conformity attestation procedures (CE marking) or, in their absence, the manufacturer's declaration based on a test report issued by an Italian laboratory authorised pursuant to the decree of the Ministry of the Interior of 26 March 1985, or another laboratory recognised in one of the European Union countries or countries contracting the EEA agreement. For the purposes of assessing the external fire resistance class of roofs and roof coverings, it should be noted that the 1st version of UNI CEN /TS 1187 was published in February 2012 to replace UNI ENV 1187:2007 cited in the technical guide. For information purposes, please note that the European Commission decisions 2001/671/EC (GUCE L 235 of 4 September 2001) and 2005/823/EC (GUCE L 307 of 25 November 2005) report the classification system for the external fire resistance of roofs and roof coverings. For the purposes of assessing the reaction to fire class of the photovoltaic panel, please note that a specific resolution was issued on 28 March 2012 by Area V of the DCPST - Fire reaction sector, on the methods of carrying out reaction to fire tests on PV panels. (Annex C). The resolution requires laboratories to issue a specific test certificate in which the use will be indicated as "PHOTOVOLTAIC PANEL". The test certificate is linked to the panel itself and not to the place of use. The risk assessments must be signed by qualified technicians registered in the lists of the Ministry of the Interior.

Checking the installation of an EI 30 panel under photovoltaic panels on a roof with the following stratigraphy: •Roofing: insulated corrugated sheet metal•Insulation: Polyurethane (PU) Rock wool (5 cm) requires the analysis of various regulatory and technical aspects. Here are the main points to consider: 1. Checking the EI 30 Fire Resistance EI 30 indicates a fire resistance of 30 minutes in terms of tightness (E) and thermal insulation (I). The EI 30 panel must be certified according to current regulations (e.g. UNI EN 1365-2 for roofs). Its installation under photovoltaic panels must guarantee continuity of passive protection against fire. 2. Compatibility with the Roof Stratigraphy Corrugated sheet metal: the presence of a cavity under the sheet metal can influence the behavior in the event of a fire. PU Rock Wool: Polyurethane is combustible and may promote fire spread, while rock wool is non-combustible and helps protect against fire. It is necessary to check whether the installation of the EI 30 panel creates thermal bridges or discontinuities in protection. 3. Local Regulations and Requirements Check compliance with local fire regulations (e.g. DM 03/08/2015 in Italy for activities subject to the Fire Brigade). If the photovoltaic system exceeds 20 kW, specific compartmentation requirements may be required. 4. Installation and Fixing The EI 30 panel must be adequately anchored to the structure to maintain its fire barrier function. Consider safety distances between the PV panels and the EI 30 panel to avoid overheating. 5. Possible System Approval It is recommended to check whether the complete system (roofing EI 30 panels PV system) has already been tested and certified as a single solution. If no certification exists, specific tests may be required to ensure compliance. Risk assessments must be signed by qualified technicians registered in the lists of the Ministry of the Interior.