DJU France: map and history by regions

[Christophe]

That's fine, but that's the purpose of mandatory ECD, no? it already gives, during a real estate transaction, a conso normalized on an average year in kWh / m².year, with a translation into euros and quantity of fuel, with also the classification letter ABCDE ... Given that the formula of calculation is normalized, the result is supposed to be relatively objective, and allow the comparison of different dwellings, and thus influence the choice of the buyer.
Unfortunately, it is still necessary that the dpe is well done, sometimes it is far in reality, but it is another problem, that of putting into practice.

Yes, but how is a real estate DPE established? Simply ... by analyzing previous energy bills... It is also realized by estate agents who can not distinguish, in most cases, kW and kWh ...

So the DPE is based more on the habits of the old inhabitants than the thermal performance of housing ...

Examples: The Hecolo family never heated more than 18 ° C sells his house with an excellent DPE based on his bills ... rated A +!

This DPE will have nothing to do with the DPE family Jmencogne who bought the house and heating it to 24 ° C: the consumption goes to G according to the same method of DPE ...

If the DPE was based on the DJU this paradox would not be possible ... but it will have required a constant measurement of the average T ° of housing ... necessarily it is harder than adding some figures on a bill.

So DPE = nice joke but it's better than nothing!

[Chartrousin]

Yes, but how is a real estate DPE established? Simply ... by analyzing previous energy bills... It is also realized by estate agents who can not distinguish, in most cases, kW and kWh ...

Nonnon, that's not the way DPE does it.

Estimated annual consumption

There are two ways of evaluating ECD for existing buildings:

* either from a conventional diagnostic method (type 3CL-DPE), valid only for units with individual heating built after 1948, taking into account the thermal characteristics of the building (climatic zone, insulation, glazing ...) and the heating and ventilation systems installed,
* from the energy bills for other cases (housing before 1948, collectively heated apartments, tertiary buildings).

In all cases, the DPE must be performed by a professional diagnostician, who has been certified to deliver DPE.

The use of invoices is only for 1948 front or tertiary buildings or collectively heated.
In addition, the diagnoser has (normally !!) an obligation of independence (he can not be a real estate agent at the same time, or heating engineer and adviser of the work he will do). Despite this, the fact is that the client of the diagnoser is the real estate agent (or the owner), and therefore he has an interest in minimizing the results ... There are not enough controls yet is safe, and for the moment the dpe is far (very) perfect.
But in theory, it responds to the need we mentioned before: to have an objective way to compare the performance of housing, regardless of occupants.

This is a conventional calculation which gives the result of the DPE. A little software, we enter the characteristics of the building, and presto we have the result. Moreover there are even boxes "does not know" which make it possible to make a calculation even when one does not know what there is like insulation (from where results sometimes aberrant!).

In any case I can assure you that on a house> 1948, the actual bills and conso are not used.

[Chartrousin]

extract from a DPE "standard report":
http://www.logement.gouv.fr/IMG/pdf/maq ... gement.pdf

Conventional consumption
These consumptions are called conventional because calculated
for fixed conditions of use (it is considered that the
occupants use them according to standard conditions), and for
average climatic conditions of the place.
There may therefore be significant differences between
energy bills that you pay and consumption
conventional for several reasons: according to the rigor of
winter or the actual behavior of the occupants,
which may deviate significantly from that chosen in the
standard conditions.
Standard conditions
Standard conditions are for the heating mode
(respective heating temperatures of day and night, periods
dwelling), the number of occupants and their
hot water consumption, the rigor of the local climate
(outside air and drinking water temperature, duration and
intensity of sunshine). These standard conditions serve
from basic assumptions to calculation methods. Some of these
parameters are the subject of unified conventions between
calculation methods.

[Christophe]

Well that's the ideal theory but the practice is much more doubtful and I believe that the “real estate” housing DPEs for individuals are far from respecting these criteria ... they are done in less than 1 hour!

There is an example of real ECD on forums, it is based on invoices only!



https://www.econologie.com/forums/exemple-de ... t5908.html

[Chartrousin]

Well that's the ideal theory but the practice is much more doubtful and I believe that the “real estate” housing DPEs for individuals are far from respecting these criteria ... they are done in less than 1 hour!

Completely agree with you. It would take a lot more controls! I do not tell you the number of completely botched ECDs I've met. The last DPE that came to my mind gave a theoretical heating consume of 9 000 kWh in a poorly insulated 120 m² house, which actually consumed more than 20 000kWh, yet occupied by very very economical people (average temperature = 17 °).

Last but not least, except for the case of collective heating or housing older than 1948, the DPE is made by conventional theoretical calculation (it is mandatory, otherwise it is not valid).

For your example, I can not tell you, I do not see the document? But it may be a house dating from before 1948 (in this case the theoretical calculation is not usable, and it is the bills that are used, averaged over 3 years).


To do a DPE in less than an hour, there is no need for invoices. You just have to check the boxes "don't know" and "default value" all over the software, and the DPE goes very very fast
Well it's not surprising, after the result does not mean much ...

[Chartrousin]

Ok I saw the document, it works now.

At the bottom, on the other pages, he wrote:
"The quantities of energy are evaluated on the basis of estimated consumption (conventional consumption)"
So it's not the bills that were used, though?

[Chartrousin]

Source of what I advance:
15 / 09 / 06 Decree, with DPE Terms, and DPE Models to Use
http://www.rt-batiment.fr/fileadmin/doc ... e_2006.pdf

[Christophe]

Well you can even chat with the new owner of the house is Flytox these forums!

[Chartrousin]

I'll ask him, but normally it's the former owner who is doing the dpe, not the new one, so he's not supposed to have seen the diagnoser doing his job ... (or not doing it ).

[Christophe]

Yes that's it, I do not think he saw it but it will surely have more info..In any case it was ULTRA light ...

Ask him the question on the other subject ...