Extensive renovations were carried out at the Nikola Tesla primary school in the Croatian city of Rijeka under an EU-funded project. Originally aimed at cutting the annual amount of energy used for heating the school by at least 20 %, the project far exceeded this target. It achieved a reduction of over 47 % or 187 538 kilowatt hours (kWh) a year: from 75.45 kWh to 39.79 kWh per m² per year.
- 21 May 2019
Energy renovation of buildings reduces energy consumption and at the same time achieves a favourable microclimate for work, extends the lifespan of the building, reduces building maintenance costs, expenditure on energy consumption and CO₂ emissions, and contributes to economic growth.
Work to improve the building’s energy efficiency included restoring the facade, replacing the exterior joinery with wood that has better insulation characteristics; and thermally insulating the roof, the terrace and the ceiling below the attic.
The improvements reduced the school’s annual CO2 emissions by 44.26 tonnes, enabling it to move from class C to class B in energy performance. They cut energy consumption and maintenance costs and extended the building’s expected lifespan.
A sustainability priority
As with many cities, Rijeka has less and less space for new developments while the condition of existing buildings is deteriorating. A large proportion of its publicly owned structures housing educational institutions were built in the early 20th century or the 1970s. In the interests of sustainability, investment in their renovation has become a priority.
Dating from 1934, the Nikola Tesla school is located in the centre of Rijeka and has protected status. The renovations were difficult due to the need to adhere to both conservation rules and new construction requirements aimed at ensuring that the coefficient of thermal expansion – how materials change size and shape when the temperature changes – is taken into account.
When undertaking energy efficiency renewal of buildings, improving the thermal performance of external walls is a good way of maximising savings. For a protected structure such as the Nikola Tesla school, the conservation laws did not allow this.
Furthermore, although the renovations were based on documentation prepared in line with applicable rules, it was impossible to anticipate all discoveries made once the project got underway. As construction methods from the 1930s differ in many respects from those used today, the project team often had to find ad hoc solutions to specific problems.
From outdated building to good practice example
The facade – particularly those parts overlooking the yard – was in very bad condition. There was damage to the plaster and joinery; the ceiling under the unheated attic had no insulation and the thermal characteristics of the building envelope did not meet current requirements. Moreover, as a lot of the work was done during the school year, the team relied on the patience and cooperation of parents and children to finish the job on time.
Following completion of the project, the Nikola Tesla school has become an example of good energy efficiency renewal practice for protected buildings. Its pupils now benefit from an education in healthier surroundings that are more conducive to learning.
Total investment and EU funding
Total investment for the project “Energy renovation of the primary school Nikola Tesla, Rijeka” is EUR 823 310, with the EU’s European Regional Development Fund contributing EUR 208 203 through the “Competitiveness and Cohesion” Operational Programme for the 2014-2020 programming period. The investment falls under the priority “Environment and resource efficiency”.