Energy efficiency in municipal buildings: Renovating the fire department of Berkovitsa, Bulgaria

Public nZEB buildings case study
Building type
Administrative Public
Project type

The fire department of Berkovitsa / © Google Street View

In 2019, the city of Berkovitsa in Bulgaria initiated an ambitious project to renovate several municipally-owned buildings and facilities, prioritising increased energy efficiency and reduced carbon emissions in their operation. The project, called “Increasing the Energy Efficiency of Buildings in the City of Berkovitsa” plan, was supported by European funding.

One of the buildings subjected to renovation was the municipal premises located in number 2 of Anton Strashimirov street, hosting the fire department, and also Berkovitsa Municipality. The building in question is a four-storey construction that was originally constructed in 1978, lacking thermal insulation on its façades and windows – walls and roof are large – falling into the class F energy consumption.  The renovation project commenced in April 2019 with the tender announcement, and concluded in December 2022, with the inauguration of the renovated building.

How was this building procured?

The tender for the renovation of the fire department was published in 2019 by the contracting authority ( i.e. the municipality of Berkovitsa). The tender outlined several key areas of action, encompassing tasks such as enhancing thermal insulation to significantly reduce heat transfer, replacing existing fixtures like windows and doors, upgrading the boiler and HVAC system, and modernising the lighting infrastructure. These efforts to reduce energy consumption were directly linked to national goals for lowering greenhouse gas emissions on the tender.

The contracting authority also incorporated a requirement regarding the contractor’s experience. It was necessary for the contractor to demonstrate recent experience within the construction industry, specifically in implementing energy-efficient measures. This included involvement in construction or repair works integrating energy-efficient practices within the past five years. Additionally, possessing various quality management and environmental management certificates was deemed essential for the successful awarding of the contract.

The technical proposal carried accounted for 60% of the criteria for contract awarding, while the price constituted the remaining 40%.

The total cost of the renovation was  BGN 682,229.49 (equivalent to EUR 349.529).  Funding for the project was secured through a combination of resources, with BGN 579,895.08 (or EUR  297.040) allocated from the European Union’s Regions in Growth 2014-2020 program and BGN 102,334.41 (or EUR 52.418) from national sources.

What are the key nZEB features?

Some of the interventions of the renovation include:

  • Enhancing thermal insulation for the external walls to decrease the overall heat transfer coefficient;
  • Applying a protective vapour barrier layer and installing mineral wool insulation in the attic floor to reduce heat transfer through the roof;
  • For windows and doors: upgrading window fixtures by replacing existing wooden frames with new PVC frames featuring five-chamber profiles and double glazing. Additionally, substituting wooden fire truck doors with aluminium roller shutters filled with mineral wool;
  • Retrofitting lighting fixtures with energy-efficient alternatives and incorporating motion sensors for improved efficiency;
  • Replacing an oil boiler and HVAC system to achieve higher efficiency;

The renovation helped reduce maintenance costs and energy and heating costs while improving the comfort and energy performance of the building. An additional effect of the measures is the cost-effective operation, which has allowed its sustainable management and maintenance over time.

Due to these different energy saving measures, the total annual energy consumption has been reduced by 107,843 MWh / year and the building fell  into the “A” class of the energy consumption scale, with a reduction of carbon dioxide emissions by 131.55 tonnes / year. It has also significantly improved the comfort of employees and citizens and reduced its operating costs by more than 70% and the heating costs by 72%.

Did the project have an impact on skills?

Although the specifications of this tender did not specifically detail criteria for training initiatives, it effectively enlisted seasoned experts for the undertaking. Placing significant emphasis on experience prerequisites conveys a commendable message within the realm of public procurement, nurturing skill enhancement within the industry. Moreover, it aids in integrating expertise in nZEB technologies into the mainstream.

Keywords: Renovation of buildings, Skills demand, Energy Efficiency Training, Sustainable public procurement, Innovation public procurement, Fire Department, Berkovitsa, Bulgaria


Find out more:
  • ЪЛГАРСКА ТЕЛЕГРАФНА АГЕНЦИЯ. (2019). Община Берковица е спечелила проект за саниране на сградата на пожарната в града. Accessed March 28, 2024. Available at:
  • Портал за обществени поръчки. (2019). Изпълнение на СМР за обект: “Въвеждане на мерки за повишаване на енергийната ефективност на сграда на държавната и общинска администрация, находяща се в гр. Берковица, ул. „Антон Страшимиров“ № 2. Accessed March 28, 2024. Available at:
  • Община Берковица. (2019). 171 „Изпълнение на СМР за обект: “Въвеждане на мерки за повишаване на енергийната ефективност на сграда на държавната и общинска администрация, находяща се в гр. Берковица, ул. „Антон Страшимиров“ № 2“. Accessed March 28, 2024. Available at:
  • Center for Energy Efficiency EnEffect. (2021). Berkovitsa – Strategy and pilot projects for renovation of the municipal building stock. Accessed March 28, 2024. Available at:

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