RCCTE was published in February 1990, and have been in force since January It applies to buildings of both residential and tertiary sectors.

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1 Title of the measure: POR3 - Regulation on the Characteristics of the Thermal Performance of Buildings (RCCTE) - Decree-Law 40/90, of February 6th General description RCCTE was published in February 1990, and have been in force since January It applies to buildings of both residential and tertiary sectors. According to this regulation, new building designs and large retrofit works with a minimum useful area 300 m 2, should thenceforth meet the minimum thermal requirements established therein. RCCTE impose conditions on building design as a means to ensure that indoor thermal comfort requirements are met without excessive energy consumption, thus preventing pathological effects that might occur, like condensation in walls. RCCTE's adopted strategy establishes the maximum allowable amounts of useful energy need to meet the nominal heating and cooling requirements (N I and N V ) measured in kwh/m 2.year, taking exclusively into consideration the building envelope. Portugal was divided into three distinct winter and summer areas (as shown in the Annex 1 and 2) taking into account the respective degree of climatic severity, i.e. the harsher climatic severity in one area, the more demanding thermal characteristics of building envelopes in that area. This affects the insulation levels (or the heat transfer coefficient) of the envelope in relation to heating requirements, and also the use of sun protections in summer (e.g. shading devices and convection through the envelope, depending on a building's inertia, orientation and colour). Reference thermal characteristics of building envelopes are established for each climatic area. Verification of conformity with the regulations can be achieved in two ways: automatic verification - when the characteristics of all critical building elements are equal or better than the reference target values; that verification is shown in the Annex 3 detailed verification - by filling out a spreadsheet in order to check whether the architectural options of the designers give rise to estimated nominal energy requirements (N Ic and N Vc ) lower than, or at least equal to, the maximum allowable threshold values established by RCCTE (N I and N V ), these values are shown in the Annex 4. This regulation has been updated. The process started in 2002 and was concluded by the end of The new RCCTE version was published in Decree Law nº 80/2006, April 4 th. Impact evaluation (methods and results) Results Between it was observed an annual average growth of 3,7 % on final energy consumption in household buildings(source: Energia Portugal 2001). However, this value must be evaluated taken in consideration the improvement in families income (in their purchase power) what reflected a larger penetration of high consumption equipment and higher comfort demands. Moreover, there was an increase in the number of dwellings, representing a growth of 10% in the period of Furthermore, it can be said that the annual average growth verified for this sector was much lower compared with the values obtained for other economic sectors (transports, tertiary, industry..). For instances, for the tertiary sector it was verified a 8,4% annual average growth on energy consumption, for the same period, which was the highest rate growth registered in all the different sectors.

2 Still, it is not possible to evaluate these measure impact, once in Portugal it was not created yet a database or other similar process to evaluate the impact in terms of energy and CO 2 savings, according with that regulation implementation. Nevertheless, after 14 years of this measure implementation, it is obvious that new aspects are now taken in consideration, in the building construction, namely the natural lighting or even the shading provided by new and innovative processes (using in same cases the vegetation as external shading). In other words, the bioclimatic construction, is currently a solution that is taken into account by architects on a project phase, in order to reduce the energy gains and losses, during the summer and winter seasons, respectively. In a synthesis report produced by the Forum "Renewable Energies in Portugal (2001) it can be highlight the following: - RCCTE regulation consisted on a first regulation (base) for improvement of the thermal quality of the building envelope in what refers the "improvement of the comfort without an additional energy consumption". This first regulation, had a significant impact in the way buildings were constructed in Portugal. - Today, after 14 years of its implementation, the majority of buildings are already using the thermal insulation and the double glazing began to be used in the good constructions. It is also important to mention that normally, when the users buy a house or apartment they are aware of the importance of the thermal insulation and the double glazing. - After 14 years of experience with the implementation of the RCCTE, the technical community is now perfectly familiarised with the thermal aspects in buildings, and therefore there are currently the conditions for an improvement in the thermal quality of buildings. Although a systematic evaluation of the energy impact of this regulation has not been conducted, it is expected that its correct application should yield significant savings. Measure Impact low medium X high Interaction of measures These measure interacts with measure POR7 (RSECE Regulation of the buildings acclimatisation energetic systems). Both regulations are applied when the buildings have acclimatisation systems. There is a mitigating interaction between both; The saving effect of heat and cooling systems regulation (POR7), becomes lower, as under the present measure, heat and cool needs are to be decreased. From RCCTE it is achieved the nominal heating and cooling requirements (N I and N V ), taking exclusively into consideration the building envelope. From RSECE it is achieved the maximum power needed for the heating and cooling equipment s.

3 Historical data Under the framework of the E-4 Programme (Energy Efficiency and Endogenous Energies), launched on September 2001 by the Portuguese Ministry of the Economy, the Decree-Law 40/90 "Regulation on the Characteristics of the Thermal Performance of Buildings (RCCTE)", of February 6th was updated and revise in order to promote the energy efficiency in buildings. The reformulated RCCTE revokes the existing one. This regulation revision was performed in accordance with Directive 2002/91/EC of 16th December, on the Energy Performance of buildings, that imposes among other conditions the periodical establishment and update of regulations for energy consumption decrease in buildings. The new RCCTE will be a more demanding tool with better control in its practical implementation. Its effective introduction is predicted to lead to an increase in thermal efficiency in new buildings. References The revision of these regulation, was elaborated by the national teamwork, created in 2002 under the P3E national program. It involved several national entities (Agência para a Energia, Faculdade de Engenharia da Universidade do Porto, Faculdade de Arquitectura da Universidade Técnica de Lisboa, Escola Superior de Tecnologia da Universidade do Algarve, Instituto Nacional de Engenharia e Tecnologia Industrial, Instituto Superior Técnico, Associações Representativas do Sector, Associação Nacional dos Municípios Portugueses, Direcção Geral de Energia e Geologia, Instituto de Meteorologia, Laboratório Nacional de Engenharia Civil, Ordem dos Arquitectos e Ordem dos Engenheiros). All the work that has been developed by the national teamwork related to the energy efficiency in the buildings sector can be provided in - PNAC (2001), Programa Nacional para as Alterações Climáticas, Comissão Interministerial para as Alterações Climáticas, IA, Lisboa; - Fórum (2002), Fórum Energias Renováveis em Portugal, ADENE, INETI - DGGE (2005), Part III. National Reporting Guidelines for CSD-14/15 Thematic Areas, Ministry for Economy and Innovation - Decree-Law 118/98, of May 7th - Decree Law 40/90, of February 6th

4 Annex 1: Map for Winter Climatic Division Last update: 2 June 2006

5 Annex 2: Map for Summer Climatic Division Last update: 2 June 2006

6 Annex 3 Automatic Verification for Winter (point 5 of the Art. 5º) - K Building K Reference Thermal conduction coefficients of reference [k -W / m 2. ºC] Envelop elements Climatic zone I 1 I 2 I 3 K External vertical opaque zone 1,4 1,2 0,95 K External Horizontal opaque zone 1, ,75 K (Glaze + Frames) (a) 4,2 4,2 4,2 (b) 5,8 5,8 5,8 (a) Buildings that have important nocturne occupation, for example, residential buildings, hotels, some zones of the hospitals, etc, which for that is applied an average thermal conduction coefficient (day-night). (b) All the remaining cases, zones without nocturne occupation. - Cold bridge factor Glazed areas 15% of the floor useful area Automatic Verification for Summer (point 4 of the Art. 6º) - K Building K Reference The same that was presented in the table above for the winter case; - To have light colour in the roof; - To have a medium or heavy thermal inertia; Inertia Class Useful superficial mass by square meter of floor area [kg/m 2 ] Weak I t < 150 Medium 150 I t 400 Heavy I t > To have glazes, for which solar factor should be 0,15.

7 Annex 4 Maximum admissible thermal conduction coefficients [k -W / m 2. ºC] Envelop elements Climatic zone I 1 I 2 I 3 External elements: Horizontal opaque zones 1,25 1,00 0,90 Vertical opaque zones 1,80 1,60 1,45 Internal elements: Horizontal opaque zones 1,65 1,30 1,20 Vertical opaque zones 2,00 2,00 1,90 Maximum admissible of the solar factors Climatic zone V 1 V 2 V 3 Building thermal inertia type: Solar factor Low 0,15 0,15 0,10 Medium 0,56 0,56 0,50 Heavy 0,56 0,56 0,50