Clarifications on energy matters
The Ministry of Economic Development has issued a series of clarifications that clarify the decree concerning minimum requirements.
Following a simplified summary of the issues that directly concern the windowmaker, revised taking into account the opinions of Samuel Broglio, Paolo Ambrosi and UNICMI.1) Parameter g
For the purpose of calculating the value of the solar gtot transmission factor, any dimming or shading system, including roller blinds and blind blind blinds, regardless of whether or not they are switched on or not, is used.
In the case of external blackout blinds, the value of the total transmission factor Gtot is automatically satisfied.2) Cassonetto
The weighted average can not be made with the window frame, but the box must also comply with the prescribed Usb value individually.
If no action is taken on the bin, compliance with no limits is not required.
3) Technical Report
For the interventions of replacing only doors and windows whose total surface is less than 25% of the gross dispersing surface, the technical report of a designer is not necessary, a declaration by the executing company is sufficient:
· Thermal transmittance of old windows (table values proposed by ENEA)
· Transmittance and air permeability of new windows
· Transmittance of the box (only if replaced)
· Solar transmission factor (if there are external blinds, the gtot value is considered already satisfied
and nothing should be documented)
· Verification of the transmittance of the new supply windows with the limit values foreseen by the Decree 20/06/2015 according to the climatic zone;
4) Thermal transmittance
The fact that compliance with the transmittance values of the windows and doors must be evaluated on the theoretical measurements provided in the tables in the annex. And of EN 14351 and not already on the actual measurements present in the supply.
The declaration of values pertaining to measurement, other than a "mandatory service" to be supplied only and only if they are necessary for the designer to calculate the heat exchange of the entire building and has no value for the purpose of respecting the values of law.