With great delay, the Italian government has finally implemented the EU Directive 2010/31 on Near Zero Energy Buildings. This directive leads the way for the future development of the entire European construction industry: let's explore what it is, shall we?
The Directive requires Member States to set minimum requirements for energy efficiency in buildings, in line with the objective of obtaining "Near Zero Energy" by 2020.
The new calculation method and the minimum requirements will be published by the summer of 2013, replacing the Legislative Decree 192/2005.
In the text of the new decree, which has yet to be published in its final form, there will be an introduction to the definition of a "Near Zero Energy Building", a statement of national energy objectives, and a description of the new method of calculation. It should also contain an intermediate energy target, more short-term, probably for 2015.
Even though we have not seen yet the official text, we want to take a moment to reiterate our concerns.
Energy certification, as it has been developed in Italy in recent years, it is not at all a guarantee for the quality of construction. Please refer to our article on this subject, titled "Why an Italian regional energy certification is not enough to guarantee the quality of a building".
Our fear is this: if the new decree defines 'Near Zero Energy' purely by means of an energy balance, the current situation will be perpetuated to the detriment of the quality of building construction and comfort of those who will occupy those buildings.
It all comes down to that definition: what is a Nearly Zero Energy Building?
Even lacking the official definition, we can make some guesses:
- A Near Zero Energy Building consumes very little power;
- A Near Zero Energy Building consumes less energy than it produces;
- A Near Zero Energy Building does not consume energy
At first glance, it seems clear: Near Zero Energy Buildings represent the ideal future of the building industry. At this point, we'd like to point out some flaws.
Here is an example of a Near Zero Energy Building:
If the definition of a Near Zero Energy Building is solely based on energy, this house shown in the image above would be considered "Near Zero Energy".
First of all, let's think about this term "near". The Tower of Pisa is "nearly" straight.
Secondly, if only an energy balance between consumed and produced energy is calculated, it's possible to make all buildings to Class A+++ by simply covering them with solar panels or other renewable energy sources. This, however, has no effect on the actual quality of the thermal envelope of the building. Even the Coliseum could be considered in a high energy class, as long as it's connected to 2 acres of photovoltaic panels.
Yet in these buildings, there will still be low temperatures and there will still be mold. Is this the future we want for our buildings?
We have already explained why we believe it is better to invest in building envelopes than in energy systems (only in Italian, translation coming soon). A PV will not eliminate mold.
In the Italian market, there are several voluntary building certification institutions, such as Passivhaus Institute or CasaClima. For many years these organizations have been developing protocols for design which ensure above all the comfort of the inhabitants, with a secondary result being high levels of energy savings. Passive houses are a prime example of this.
The question is whether or not the Italian government will have the foresight to learn from these organizations' years of experience.
Our opinion as designers is this:
The ideal building standard for the future of the construction industry in Italy is not Near Zero Energy, but Passive (read more).
*Note: This article, as well as the rest of our blog, is primarily written with residential architecture in mind. However, we can also illustrate the passive building concept for other building types.