When you decide to join the "Exoikonomo" programme to replace your old windows, your mind immediately goes to finding the ideal aluminium manufacturer. You search for designs, colours and mechanisms.
Yet there is one person who is far more important at this stage. They are the "director" of the entire project - the person who holds the key to opening (or shutting) the subsidy tap. That person is the Energy Inspector.
The inspector (usually a qualified engineer) is not a simple paperwork processor. They are the scientist who guarantees the state that the money it gives you will be put to good use. Let us see exactly how they shape your window choice through the two Energy Performance Certificates (EPCs).
The EPC is essentially your home's "energy identity card". Just like the coloured sticker you see on new refrigerators or washing machines (from green A to red H), exactly the same system applies to buildings.
The "Exoikonomo" programme requires two such certificates: one at the beginning (before you do anything) and one at the end (when the work is finished). The first determines what you need to do and the second proves you did it correctly.
The scale runs from A+ (excellent) to H (very poor). Homes with old windows and zero insulation typically fall into categories E, Z or H. These are exactly the categories that form the main "audience" of Exoikonomo.
Before you even submit your application to the platform, the Energy Inspector visits your home. They measure the walls, inspect your old windows (e.g. single glazing, air leaks through the aluminium), check your heating system and enter the data into specialised software.
The software produces the home's current rating (e.g. Category Z - very poor). This is where the most critical step takes place: Setting the Energy Target. The inspector simulates various interventions in the software to see how the home can climb up the categories (e.g. from Z to C).
The inspector draws up the Intervention Proposal Form, which effectively says: "To reach the target and get the money, the homeowner must install new windows with an overall thermal transmittance (Uw) below 2.0 W/m²K." That number is the law.
The Uw number written by the inspector is the law. When you visit your aluminium manufacturer for a quote, it is not enough to say "I want nice double glazing." You need to hand over the inspector's specifications!
The manufacturer must propose an aluminium or PVC system that (combined with the right energy glazing) meets or exceeds the 1st EPC specifications. If they install a cheap series without a thermal break that has Uw 2.8, the system will "fail" you.
If the manufacturer installs a cheap series without a thermal break with a Uw of 2.8 instead of the required 2.0, the 2nd EPC will show that the target was not met. The consequence? You lose the entire subsidy and pay everything yourself.
Once your wonderful new windows have been installed, the Energy Inspector returns for the second survey. This is your "exam."
They verify that the declared windows were actually installed. They ask the manufacturer for the Declaration of Performance (DoP) and the CE marking of the windows. These documents officially prove the insulation coefficient achieved. The data is entered into the system and the 2nd EPC is issued.
If the 2nd EPC shows that the energy target (set in the 1st EPC) was achieved, congratulations! The Ministry gives the green light, the file is closed successfully and the bank disburses the subsidy funds to the manufacturer.
If for any reason you went your own way, or the contractor installed inferior materials, the 2nd EPC will show that the home was not sufficiently upgraded. In this (rare but real) scenario, you are excluded from the programme and lose the entire subsidy! You are called upon to pay 100% of the invoices out of pocket.
The Energy Inspector is not merely a bureaucratic "obstacle" - they are your most valuable ally in the Exoikonomo process. They will ensure you are not misled and that the windows you pay for (even with a subsidy) are truly capable of keeping your home warm.
Listen to them carefully and hand over the study details directly to your manufacturer before closing any deal! The Uw that your engineer sets in the 1st EPC will determine the aluminium series, the glazing, and ultimately the cost.
Return to category.
Go to categoryReturn to the central guide.
Go to guide
