Case Studies

Renovation of an apartment in a multi-family build

Cholargos, Greece

Code: CS3

View from the outside

Original situation

A multifamily house of the 80’s, of 1500 m2 treated floor area, with light insulated brick façade and a floor slab 2,4m above ground, non-thermally broken aluminium windows with double glazing, an airtightness level of n50=8 ACH, 150m2 balconies and a flat uninsulated roof.

Renovation approach

Design phase in progress: PHPP planning

Modernisation proposal

The aim will be to reach the EnerPHit standard for the whole building using the step by step methodology and renovating in the first step one apartment in the first floor.

Efficiency improvement

According to the retrofitting plans, heating demand will be reduced by a factor of 10 and cooling demand by a factor of 5.


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Key facts

Building typology

Multi family dwelling

Existing treated floor area (usable floor space)

140 m2

Building owner

12 owners

Consulting outphit partner

Hellenic Passive House Institute (HPHI)

Project status

Planning phase

Overall budget

38 000 €


Dimitris Pallantzas
Hellenic Passive House Institute (HPHI)
Phone: +30 211 4081109