thumb image

Flanders adjusts energy performance requirements

Together with Bauphi and RHDHV, VK Architects & Engineers again applies itself to the “Study of the cost-optimal levels for the minimum energy performance requirements of non-residential buildings” of the VEA (Vlaams Energieagentschap, Flanders’ energy agency). The previous study from 2015, also with the cooperation of VK, was a success.

Adjusting the road map of cost-optimal energy levels

In order to ensure that the presupposed energy performance requirements remain feasible and affordable, every two years in Flanders, a new study on cost-optimal energy levels is realised. When necessary, the presupposed path is adjusted. In 2014, the Flemish Government sharpened the path for energy levels of offices and schools: E55 by the year 2016, E50 by 2018, E45 by 2020 and E40 by 2021 (NZEB or nearly-zero energy buildings). Based on the evaluation of the energy performance regulations in 2015, and the study which was performed for that purpose, the Flemish Government establishes the road map for all types of non-residential new buildings and thorough energy renovations.

 E-eis functie  2017   2021 
 Accommodation function 80 70
 Offices 55 50
 Education 55 55
 Healthcare with stay 80 70
 Healthcare without stay 80 65
 Healthcare operating rooms 60 50
 Meeting high occupancy 80 65
 Meeting low occupancy 80 65
 Meeting cafetaria/dining facility 70 60
 Kitchen 70 55
 Retail 70 60
 Sports: sports hall, gym 65 50
 Sports: fitness, dance 65 40
 Sports: sauna, swimming pool 65 50
 Technical rooms 55 45
 Communal 55 50
 Other 85 80
 Unknown 85 80


As the main target, the study for cost-optimal levels is to obtain a detailed analysis of the total costs against the total primary energy consumption of a number of packages of energy-saving measures (architectural and technical), that are applied on a set of reference buildings and building units. This analysis is calculated using the method for non-residential buildings (EPN calculation method). In that way, the cost-optimal and cost-effective levels of requirements can be determined. The obtained cost-optimized levels are then compared with the current and planned energy performance demands for new buildings and thorough energy renovations with regard to building units and building types, giving the Flemish Government the opportunity to check the existing and planned energy performance demands against the cost-optimized levels.

Reference buildings

In the cost-optimisation study from 2015, various scenarios were calculated for 11 buildings with a total of 26 functions. These buildings were selected by the VEA (Flanders’ energy agency) from their existing database. In the ongoing study, new projects were selected from VK’s portfolio. These reference buildings were selected from an extensive number of diverse projects, to which VK contributed the past years in various disciplines (M&E engineering, sustainable design, energy reporting, structural engineering, architecture …). As a result, from the various functions in the EPN-method, 38 functions can be found in 11 buildings.

  • Office building KOP Beneluxpark – POLO Architects
  • Laboratory Red Cross Mechelen – POLO Architects
  • School Henleykaai – Bel-architecten & Bob McMaster Architecten
  • University College Artesis Antwerp – POLO Architects & Jaspers-Eyers Architects
  • Retail space Kouterdreef – B2Ai
  • Showroom Reynaers – Jaspers-Eyers Architects
  • Swimming pool Heist op den Berg – LD architecten
  • Hotel Sterea – SUM
  • Nursing home Zwevezele – VK Architects & Engineers
  • Hospital ZNA – VK Architects & Engineers
  • Library South Boulevard – Goedefroo + Goedefroo Architecten & Robbrecht en Daem Architecten

The selected buildings are representative for Flanders’ buildings market. They are in the design phase, under construction or were completed in the past 5 years. The typology and geometrical properties of the selected reference buildings were compared to properties of buildings from the energy performance database and VK’s project list.

As a result, the list shows an equal spread of both large and small buildings, compact and less compact volumes, with various function lay-outs and glazed surfaces. Glazed surface is also a variable in the measures to be researched. Moreover, the 11 buildings from the earlier study will be included in the final analysis, introducing in the end 22 buildings and 64 functions into the study for cost-optimized energy performance levels.

Consultation with the construction sector

On Tuesday April 18th, the benchmarking of the reference buildings and the cost-determination of the various measures were explained on a stakeholders meeting. Several parties from the construction sector could ask questions and propose recommendations, which will be taken into account in the study. The final report of the study will be published by the VEA (Flanders’ energy agency) at the end of 2017.