{"id":3462,"date":"2017-01-26T11:07:45","date_gmt":"2017-01-26T10:07:45","guid":{"rendered":"https:\/\/www.gate-away.com\/blog\/?p=3462"},"modified":"2024-12-27T15:53:59","modified_gmt":"2024-12-27T14:53:59","slug":"expert-building-energy-efficiency-rating-explained","status":"publish","type":"post","link":"https:\/\/www.gate-away.com\/blog\/expert-building-energy-efficiency-rating-explained\/","title":{"rendered":"Home Energy Efficiency in Italy Explained"},"content":{"rendered":"\n

While searching for your dream home in Italy, how many of you have ever asked yourselves about the exact meaning of those \u201cstrange acronyms, letters and numbers\u201d appearing in many real estate ads on Gate-away.com, as well as in many other websites?<\/em><\/p>\n\n\n\n

They represent the energy efficiency level of a building<\/strong>. Okay, maybe you already knew it\u2026 but what is their purpose and how to interpret them? The issue could become a bit more complicated.<\/em><\/p>\n\n\n\n

We will try to explain it with the help of Andrea Salcone<\/a><\/strong> from \u201cDesign? Studio Associato\u201d<\/strong>, engineer and energy efficiency expert.<\/em><\/p>\n\n\n\n

1. Why is the energy efficiency level of a property listed in a real estate ad?<\/h2>\n\n\n\n

“Energy performance certification of buildings in Italy was introduced following recent European directives aimed at reducing energy consumption<\/strong> in the states belonging to the EU and at introducing the \u201cenergy efficiency\u201d parameter, a new criterion in the property market. So since 1 January 2012 it is mandatory to provide each building with the energy performance certificate,<\/strong> called APE in Italy<\/strong>, when a home is put for sale or for rent.”<\/p>\n\n\n\n

2. What is exactly an Energy Performance Certificate (APE)?<\/h2>\n\n\n\n

“The APE is a very important document for potential home buyers and people looking to rent a property as it provides information concerning energy consumption in buildings and recommendations on where you could make improvements<\/strong>. It also includes data on winter and summer air conditioning systems, hot water production for sanitary uses and ventilation. Furthermore it analyses the ability of walls and floors that separate a heated room from the outside or from unheated rooms to retain the heat within the building.<\/p>\n\n\n\n

That is why in any property advert \u2013 even if regarding a property for sale without any heating system, such as beach houses, historic homes or properties without a boiler \u2013 one must show the energy class and the energy efficiency value, both listed in the APE.<\/p>\n\n\n\n

Starting from 1 October 2015 the new APE has replaced the former certificate<\/strong>, so that now each building is assigned a specific energy class represented by a scale of 10 levels ranging from A4 (the most efficient), A3, A2, A1, B, C, D, E, F to G (the least efficient)<\/strong>. On the contrary, before 1 October 2015 the letters used were A+, A, B, C, D, E, F, G.<\/p>\n\n\n\n

In any case certificates following the former method and issued until the end of September 2015 are still valid for 10 years from the date of issue as long as in the meanwhile the building has not been altered so a new certificate will be required. So we are in a transition period in which new and former energy performance certificates are not directly comparable.”<\/p>\n\n\n\n

3. Can you tell us how to read house energy ratings in a real estate advert?<\/h2>\n\n\n\n

“As you will notice, in property ads the energy class<\/strong> is represented by an alphanumeric value where the letter A is the most energy efficient (lower energy consumption), while the letter G the least (highest energy consumption). House energy ratings, as it happens with household electrical appliances, help you to determine the best \u201cproducts\u201d, namely the property with highest building standards in terms of consumption. This means that the higher the class (e.g. A), the more economic it is to keep a comfortable environment inside the house.”<\/p>\n\n\n\n

“The energy class scale is not fixed, but is established based on the global energy performance index value \u201cEP\u201d<\/strong> (primary energy) of a \u201creference building<\/strong>\u201d. What does that mean? That every building for which an APE is issued it is evaluated by means of the comparison of its performance with that of its \u201creference building\u201d, that is an identical building in geometrical terms (surface, volumes, location, orientation, end use, etc.) but with \u201cstandardised\u201d walls, fixtures and systems, comparable to that which our building would have if should it be built today with insulated building structures and systems of the same type, but with insulation and performance typical of the actual equipment.<\/p>\n\n\n\n

For this reason the energy class alone does not supply sufficient information to compare two different buildings, because their \u201creference buildings\u201d used for the calculation will also be different, and therefore \u201cthe scale\u201d deriving from that.<\/p>\n\n\n\n

In fact, the energy class is supplied also with a numeric value which gives the measurement of the building\u2019s energy consumption, and perhaps this is the parameter to which we should pay more attention.”<\/p>\n\n\n\n

Find your dream home in ITALY >> <\/span> <\/a><\/div>\n\n\n\n

4. In what sense is the numeric value of the rating the most important parameter? Why should we be more concerned with that?<\/h2>\n\n\n\n

“Well, the value of the energy efficiency rating (EPgl,nren) gives us the numeric value, under reference conditions, of the building\u2019s energy consumption and refers to the consumption of non-renewable energy sources, like the gas used for heating the building or producing hot water.<\/p>\n\n\n\n

The rating is expressed in kWh\/m\u00b2 per year and indicates the kilo-wattage of energy required by the building under standard conditions for every year and every square metre of floor-space heated. This value can be translated into money once the energy source used, and the cost of it, have been defined.”<\/p>\n\n\n\n

5. But how do we manage to compare the consumption of two different buildings and choose the one which will see us spend less from an energy point of view?<\/h2>\n\n\n\n

“Let\u2019s do a practical example!<\/strong><\/p>\n\n\n\n

Suppose you are interested in buying a 100 m\u00b2 property with energy efficiency rating of 53.44 kWh\/m\u00b2 per year and uses a natural gas condensing boiler.<\/p>\n\n\n\n

Now to make the calculation simple, but still indicative overlooking some technical details, let\u2019s consider that 1 m\u00b3 of natural gas is equivalent to about 38 MJ (megajoules), that is approximately 10 kWh, and on average is sold to us at \u20ac 1.<\/p>\n\n\n\n

>> Then the property in question will require for heating and hot water production 53.44 kWh\/m2 x 100 m2 = 5.344 kWh.<\/strong><\/p>\n\n\n\n

At this point we can easily calculate the m\u00b3 of gas we will need: 5.344 kWh \u00f7 10 kWh\/m3 = 535 m3 which at 1.00 \u20ac\/m\u00b3 will therefore cost us \u20ac 535 per year.<\/strong><\/p>\n\n\n\n

The real value though will differ based on our habits (temperature set on the thermostat, amount of hot water used, etc.) and on periods with anomalous weather conditions, but normally it will not move too much from our hypothesis.<\/p>\n\n\n\n

A similar thing can be said on changing the energy source, or its price, obtaining different costs, but the initial parameter for the calculation is always the numeric value of the energy efficiency index, which undoubtedly represents one of the most important pieces of information contained in the APE.”<\/p>\n\n\n\n

6. When is the APE required?<\/h2>\n\n\n\n

“By law there are specific cases in which APE is mandatory. Here are the main examples:<\/p>\n\n\n\n