Is there a limitation on the simplified method when writing an Energy Certificate?
Since recently some Energy Certificate with a «C» rating is appearing through the simplified method in existing buildings. We have wanted to provide a series of references to determine that such qualification is not consistent through the CE3 and CE3X (Simplified Method) programs according to current Regulations.
It follows from the Royal Decree Project that:
CHAPTER II (Technical and administrative conditions) Article 4. Qualification of the energy efficiency of a building - Point 2.B.
The simplified option: prescriptive in nature, which indirectly develops the calculation methodology of Annex I. The scope and development of this option will be the one that appears in the recognized document "Conditions of acceptance of the simplified option of energy qualification of buildings" prepared jointly by the Ministry of Industry, Energy and Tourism and the Ministry of Development.
You can find the document reference HERE. That the following conclusions and limitations emerge:
1.1 Maximum rating D - Minimum E (95% of existing homes in Spain)
1.2 The simplified option may be used when the percentage of openings in each façade is less than 60% of its surface.
1.3 It may be used when the percentage of skylights is less than 5% of the total roof area.
1.4 Percentages of openings greater than 60% are allowed in those facades whose area represents a percentage less than 10% of the total area of the building facades.
1.5 Those buildings whose enclosures are made up of non-conventional constructive solutions, such as “Trombe” walls, “parietodynamic” walls, attached greenhouses, etc. are excluded.
I quote verbatim the section that I think is more interesting (Page 7 Limitations):
"Point. 4 The use of this simplified option only allows to obtain energy efficiency classes D or E, although it is possible that with the use of the general option in the same building, either with the CALENER reference computer program or with any alternative computer program that has been validated, a better energy efficiency class is obtained than that assigned by this option. "
It should be noted that the simplified option strictly complies with section HE-1 of the Technical Building Code (Limitation of Energy Demand). You can find it HERE. In consideration of these limitations, the Manual for both programs indicates:
USE OF THE PROGRAM: (Scope) The simplified certification procedure for existing buildings and the accompanying computer program is applicable to all types of existing buildings except for those that have components, elements, equipment or systems not included in the CALENER reference program .
As of today, according to current legislation, we cannot calculate a home with a “C” rating using the simplified method. That the program allows it, yes. That things are not clear according to what is indicated in the program manual, well too!… But I understand that following current legislation it is only possible to perform the calculations of the simplified method for homes with a D-E rating, which are the majority of flats in Spain.
It is true that the HE does not expressly indicate that the simplified method is only for DE (It is a series of data-calculations extracted based on HE-1, HE-2 … and others) but that the Royal Decree Project refers to Its limitations have indicated that the "Conditions of acceptance of the simplified qualification option" must be met. Obviously there is no control body for Energy Certificates of existing buildings through the Administration that can correct a misapplication of the method.
IMPORTANT NOTE: READ THE COMMENTS, THEY ARE OF GENERAL INTEREST
I think you may also be interested in the discussion thread on Linkedin HERE (It no longer works)
