The Innova Project - a New, Innovative Method for Carrying Out Energy Efficient Renovations on Multi-Storey Buildings

Renovation to passive house level with timber-frame elements in InnovaIn the Innova project, a typical multi-storey house from the 1970s was renovated to meet the Finnish Passive House requirement, that is, the heating energy demand after the renovation is, at a maximum, 25 kWh/m²a. The four-storey-high building, originally constructed in 1975, is located in the Peltosaari area in Riihimäki, and has 33 rental apartments and a day-care centre. 

 

The Innova project started at the beginning of 2010 and aimed to motivate housing cooperatives to carry out energy efficiency improvements. The project searched for innovative methods and solutions for energy efficiency upgrades of the existing building stock.

In August 2010, a four-storey 33-apartment rental building in Riihimäki, built in 1975, was selected for the Innova renovation solution. The existing facades were prefabricated concrete sandwich elements, characteristic for the area.

The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings  The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings
The multi-storey house in Saturnuksenkatu 2, Riihimäki shown before renovation  During the renovation the prefabricated elements are fitted into place using a crane. This new method of renovating quickly gives the building passive-house standard.
                                                        

The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings

The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings

The prefabricated elements are completed at the factory. 

The renovation includes new doors and windows, balconies, additional thermal insulation and new ventilation system with effective heat recovery. The ventilation unit is equipped with filters to prevent problems with minor infiltration of the exhaust air and the incoming air in the rotating heat exchanger.

Laser scanning measured the exterior of the building and modelled the dimensioning of the elements. The outer concrete pane and the thermal insulation of the old exterior walls were dismantled and replaced by vertical facade elements with a wooden frame structure. The ventilation ducts, windows and the balcony doors were installed in the elements, as the first layer of the plaster rendering of the facades. The elements are transported in horizontal position and will be turned by the crane. The model element was tested at the element factory before the manufacturing was started.

Reduced on-site time 

The new renovation method reduces the duration of the on-site construction work. The entire construction phase is planned for completion in five months, which is half the time compared to the respective renovations of similar multi-storey houses in the Peltosaari area. Retrofitting is also an opportunity for up-grading the architecture of the building.  

 

 New facade

Image: Kimmo Lylykangas Architects. 
External link: Kimmo Lylykangas Architects website

 Innova facade
Facade in March 2012. Photo: Jukka Sevon, Paroc OY

The new façade materials are plaster rendering, cement fibre board (day-care centre) and wood cladding (balconies). The 3-dimensional surface of the plaster rendered façade and the variation of colour show the division of apartments behind the façade. The target of the architectural design was to upgrade the facades, but still maintain a connection to the original character of the building.

Developed renovation technique

The selected renovation system further develops a technique that has been used in retrofit projects in several European countries. In Finland, the method was introduced through the research project TES – Energy Facade by Aalto University, NTNU (Norway) and TU Münich (Germany, coordinator) in 2008–2009 [2]. The Innova project is the first known application on an existing building in Finland.

The Innova project is supported by ARA (the Housing Finance and Development Centre of Finland), Sitra (the Finnish Innovation Fund) and TEKES (the Finnish Funding Agency for Technology and Innovation), as well as several industrial partners, including Recair, Ensto, Lammin Ikkuna and Paroc as the project owner and coordinator. Expert consulting and monitoring after the renovation was carried out by VTT, Technical Research Centre of Finland. Architect SAFA Kimmo Lylykangas was responsible for the architecture and the solution itself. He has participated actively also in the TES-project in Europe.

The Paroc Innova Project - a new, innovative method to carry out energy efficient renovations on multi-storey buildings 

The PAROC Innova solution 

Structural layers:
- Old inner sheath
- PAROC UNM 37pz, 100 mm
- Tyvek fabric , XMW 060
- LVL element insulated with PAROC eXtra plus, 300 mm
- Cement-based building board
-
PAROC FAL 1 plaster base insulator, 50-100 mm
U-value 0.10 W/m2K

Structure of the timber element used in the Innova
renovation project and interface with the old structure.

Reduction of CO2 emissions

The Innova project’s passive level energy refurbishment solution in the Riihimäki pilot building enables the reduction of CO2 equivalent emissions by up to 75 tonnes per year for a typical target building. This is the equivalent of driving around the world 11 times in an average-sized car.


Read more

The Innova project has been introduced at several seminars in Finland and internationally. 
Paroc Promise Kimmo

Download the full report written by architect Kimmo Lylykangas (pdf, 0,8 Mb) >>.