Case Study: nZEC - Energy refurbishment of 30 dwellings in Õismäe Street, Tallinn, Estonia (UNDER MONITORING)
Name of organisation: EKÜL - The Estonian Union of Co-operative Housing Associations
Stage of development: completed
Year of finalization: 2011
Type of project: refurbishment
Area: urban
Scale: individual buildings
Type of building: Apartment in a block of five or less stories
Number of units/dwellings: 30
Tenure: shared ownership/cohousing
Street: Õismäe tee 11
Postcode: 13514
City: Tallin
Region/ County: Harjumaa
Country: Estonia
Last Update: 03.03.2015
Short Description
The project was carried out because of high price for heat and uncomfortable indoor climate. Heating system was one pipe system with no possibility to regulate on the radiator level. Ventilation was designed as natural from windows, but due to the fact that most of the apartments have already changed windows the natural ventilation does not worked properly any more. Heating system was unbalanced and heat supply to the radiators was unstable. At the same time support scheme for renovation was available.
Scheme terms were connected with energy saving % compared with last 3 years consumption. 25% investment support means 40% energy savings and 35% investment support means 50% savings. Association general meeting decided to go on 35% investment support. Flat owners are partly pensioners with reasonable low income (about 300 EUR month). Conditions foreseen that renovation should consist from total insulation of all external walls (U value 0,2) and roof (U value 0,15), installation of windows with U value not higher than 1,1. Heating system should be regulated on the radiator level, ventilation should have heat recovery element. Renovation project was designed for these conditions.
Key Elements
Certification
Energy certificate issued after energy audit.
Project Management
Building energy audit, preparing refurbishment plans, selecting cost-effective and energy efficient refurbishment options. Monitoring service quality.
Funding
Energy efficiency measure | Ir | Iee,brutto [€] | Iee,netto [€] | Life time [years] |
[€] | ||||
1 Additional insulation for all external areas (roof 200 mm, walls, fundament with 150 mm of insulation) |
| 70 000 | 35 000 | 40 |
2. Replacement of all old windows (U value more than 2 replaced with U value less than 1,1) | 9 000 | 4 000 | 30 | |
Glazing of balconies |
| |||
|
| 30 | ||
3 Sun panels for hot tap water |
| 26 000 | 26 000 | 25 |
4 Heat recovery ventilation system installation (room based system) |
| 45 000 | 45 000 | 20 |
Total |
| 150 000 | 110 000 |
|
Running costs |
| 4 774 | 4 774 |
|
Simple pay back time |
| 31 | 23 | 30 |
Work with Residents
This project is a good example for other neighbouring buildings. Site visits together with community members.
Partnership Working
Private energy auditing and public research (general study about apartment block houses renovation) from Tallinn Technical University for typical block houses.
Thermal Insulation
Thermal insulation system (insulation + cover), elimination of thermal bridges with full insulation.
Air Tightness
Not tested, but practically improved after renovation.
Windows and Shading
New windows have been installed with U value max 1,1, shading device can be classified the windows for balconies.
Ventilation
Mechanical ventilation with heat recovery device inside the wall.
Heating and Hot Water
District heating and sun vacuum pipes for hot tap water.
Solar Thermal
Hot water vacuum pipes on the roof.
Monitoring
Click here to access the monitoring data on the HIVE Database!
Main Results
- The most important is that flat owners got comfortable living with high quality indoor climate. The apartment’s value is higher and house main constructions are now protected and there are no thermal bridges. Ventilation system will use exhaust air heat, part of the hot tap water is produced from sun, and heat consumption is 50% less than before.
- The solar panels for hot tap water brings into the house energy balance positive renewable energy. During the period from 2010, and after the complex renovation was done in 2012, till 2014 the energy consumption for space heating drops from 94 kWh/m² to 47 kWh/m², means 50%.
Lessons learned
Additional Information
Ms Anu Sarnet
EKÜL - The Estonian Union of Cooperative Housing Associations
E-mail: anu.sarnet@ekyl.ee
Web: www.ekyl.ee
