Following the renovation of its head office in Amersfoort, Royal HaskoningDHV improved the energy efficiency of the building from a class G to a class A label. For a large office building constructed in 1970, achieving an energy performance similar to that of the current new building, is a unique result requiring an innovative approach.

Basic principles

This sustainable renovation was based on several cast-iron principles:
  • Boost energy savings.
  • Maintain excellent user satisfaction.
  • Comply with current demands in terms of fire safety and manageability.
  • Stabilise the running costs of the building.
  • Lifespan and function of the building are key to the design.
  • Bring energy-saving measures and sustainable energy sources in line with the management of the building.
  • Choose materials with a minimum environmental footprint and monitor the use and waste disposal phase.


The integral design includes a wide range of measures which together create a sustainable office building.
  • The new fully glazed facade, with HR++ glass, combines improved daylighting with solar-controlled sunblinds, providing energy savings and extra comfort.
  • The large roof has extra insulation and is finished with a light-coloured roofing material. Besides the added comfort and energy savings on heating, this makes the building cooler in summer and reduces the need for air conditioning.
  • The lighting is equipped with presence detection and daylight circuiting, thus saving energy.
  • Intelligent and energy-efficient climate control systems with low temperature heating and high temperature cooling recovers heat and moisture from ventilation air for reuse.
  • Reuse and application of sustainable materials reduce the impact on the environment and surroundings.
  • Innovative fire compartmentation with water mist screens optimise fire management.


The integral design incorporating a wide range of measures provides outstanding results. Bringing the energy label from class G to class A in this way saves Royal HaskoningDHV €100,000 on energy costs every year. The annual running costs of the building will not rise. This renovation has raised the energy performance level of the office to the current requirements for new buildings. However, the investment on a new building would have been four times as much. The sustainable renovation of the Royal HaskoningDHV head office provides the proof: even with a standard budget, the renovation of an old building can provide both increased comfort and energy savings. In 2016 the head office was certified with BREEAM In Use on level Excellent, which proves that the building and the use of the building, is highly sustainable.