Case Studies
Renovation of an apartment in a multi-family build
Cholargos, Greece
Code: CS3
Original situation
A 1980s multifamily house with a treated floor area of 1500m2, a lightly insulated brick façade, 150m of balconies, a flat, uninsulated roof and a floor slab that is 2.4m above ground. The windows are double-glazed with aluminium frames that are not thermally broken. The building is quite leaky with an airtightness level of n50 = 8 ACH (as compared to 0.6 ACH for the Passive House Standard).
Renovation approach
Under construction:
At the moment, the external insulation needs and the roller blinds need to be installed. The last one out of the 3 ventilation system needs to be installed. A blowerdoor airtightness test and ventilation protocol are also in the works. The postmonitoring is being set up at the moment as well.
Modernisation proposal
EnerPHit Energy Demand Method. This means that we will achieve EnerPHit level energy demand (25 kWh/m2a) certification by insulating the entire envelope, minimsing existing themal bridges, replacing windows, improving airtightness and installing mechanical ventilation with heat recovery.
This project will be carried out as a step by step renovation.
Efficiency improvement
Renovation will reduce the heating demand by factor of 17.5 and the cooling demand by a factor 3.5.
PHPP verification sheet before retrofit
| TFA | existing treated floor area (usable floor space) |
140.0 m2 |
|---|---|---|
| Space heating | Heating demand |
210.0 kWh/(m2a) |
| Heating load |
93.0 W/m2 |
|
| Space cooling | Cooling & dehum. demand |
41.0 kWh/(m2a) |
| Cooling load |
41.0 W/m2 |
|
| Frequency of overheating (> 25 °C) |
– % |
|
| Frequency of excessively high humidity (> 12 g/kg) |
91.0 % |
|
| Airtightness | Pressurization test result n50 |
1.0 /h |
| Non-renewable Primary Energy (PE) | PE demand |
591.0 kWh/(m2a) |
| Generation of renewable energy (in relation to projected building footprint area) |
352.0 kWh/(m2a) |
PHPP verification sheet after retrofit
| TFA | existing treated floor area (usable floor space) |
140.0 m2 |
|---|---|---|
| Space heating | Heating demand |
12.0 kWh/(m2a) |
| Heating load |
10.0 W/m2 |
|
| Space cooling | Cooling & dehum. demand |
12.0 kWh/(m2a) |
| Cooling load |
10.0 W/m2 |
|
| Frequency of overheating (> 25 °C) |
– % |
|
| Frequency of excessively high humidity (> 12 g/kg) |
3.0 % |
|
| Airtightness | Pressurization test result n50 |
1.0 /h |
| Non-renewable Primary Energy (PE) | PE demand |
89.0 kWh/(m2a) |
| Generation of renewable energy (in relation to projected building footprint area) |
43.0 kWh/(m2a) |
Video
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 €
Contact
Dimitris Pallantzas
Hellenic Passive House Institute (HPHI)
Phone: +30 211 4081109
E-Mail: info@eipak.org