Business Garden

Business Garden

Business Garden is a groundbreaking project to renovate an old government building with the worst energy label G and 4300 m2 office space, into the first WWF-certified climate-neutral project in the Netherlands with energy-positive status A +++ and 6000 m2 of living, working and conference space. It is in a prime location directly opposite the entrance to Amersfoort Central Station and is a calling card for the city. The old building will be enclosed in a climate shell with 1800 m2 solar panels on the roof and the facades and roofs are insulated with a thick layer of cork and plants.

In a nutshell...

  • Stationsplein 14-16, 3818 LE, Amersfoort opposite the entrance of the train station. Dominant and visible place on the square. Top location!
  • The current building is 4038 m2 gross with 3430 m2 rentable space. Built 1971-1973 with energy label G. After the renovation: 4900 m2 gross with 4160 m2 internal lettable space + 1.000 m2 under glass + 750 m2 garages. Energy label A +++.
  • Project costs €9.5 million all-in. ROI 7.5% plus tax benefits for Dutch taxpayers. Ground is 1970 m2. After the renovation: space for 12 visitors cars + 30 electric pool cars + 170 bicycles. Double function: offices plus living.
  • 1,800 m2 of solar panels meet all internal energy needs, in combination with passive solar heating inside climate shell. Surplus energy used to charge electric cars and compensates over 30-40 years for the carbon content of the renovation and all materials, making it the first real climate-neutral redevelopment of the Netherlands.


The total project costs are €9.5 million including land, redevelopment, construction, interior fitting, energy and water infrastructure, fees and permits, financial costs and a margin for unscheduled costs. The rent is €145/m2 per year plus approximately €30/m2 in service costs. The business case is built on a ROI of 7.5% plus a significant tax deduction for investors who pay tax in the Netherlands. A special legal framework has been drawn up in which the legal ownership of the property rests in a separate charitable foundation with a sustainability objective (giving tax deductions for investors) and economic ownership is vested in a Fund for General Account in which investors place their money. This combination of legal instruments gives investors the optimum return.


In 2014, One Planet signed lease contracts and Letters-Of-Intent for 60% of the space in Business Garden, including all 26 apartments. More parties were waiting to sign lease contracts as soon as it became clear the project was going ahead.


The project manager is Paul Heistein. We have a multifunctional team with expertise in; real estate development, rentals, financing, construction and technology, energy, architecture, marketing, facility management, taxes, legislation, subsidies, construction, specifications, contracts.

The search for sustainability

The design of Business Garden has grown step by step, each time with a higher level of sustainability. The first design had well-insulated facades and 800 m2 of solar panels. Finally, One Planet opted for the highest level of sustainability, which is climate neutral. The building is completely enclosed in a climate shell (providing passive heating from the sun) with 1800 m2 of solar panels on the roof to generate electricity for heat pumps, lighting, electrical equipment etc. The surplus electricity generated on-site over and above the needs of the users, must be sufficient over 30 years to offset the CO2 emissions of the entire renovation project and materials. This makes the project unique in the Netherlands.

Contact    tel. (+31) 06-52401947

The partnership falls apart

At the end of 2015, the collaboration between One Planet and the commercial developer suddenly fell apart on the day that One Planet was to purchase the building from the government. One Planet had exclusive purchase rights on this building at a very good price. Her sustainable Business Garden plan had already been approved by the municipality. We already had tenants for 60% of the spaces. But the developer with whom One Planet entered into a partnership for the financing and construction of the project, tried at the last moment to force One Planet into a completely different plan than we had agreed on and signed. He had silently hired another architect - out of sight of One Planet - to draw up a completely different plan to transform the building into commercial apartments, without the sustainability features One Planet had incorporated. He calculated that his plan would bring him higher profits and - knowing that One Planet did not have the money to buy and develop the building herself - he gambled on One Planet caving in to his plan at the last minute. However, both One Planet and the municipality refused to bow to this commercial opportunism. The municipality introduced a 'poison pill' into the purchase contract, so that anyone who bought the building with One Planet and did not complete the One Planet plan, would later receive a heavy fine. After four years of careful planning and preparation, greed had ruined the best sustainability project in the Netherlands. The developer then withdrew from the project and in 2017 the municipality itself bought the property from the government, with the intention of selling it in 2018-19 on the open market, under conditions of high sustainability and iconic architecture. The Business Garden plan is warmly supported by local residents. If a new owner wants to use the experience of One Planet, he or she may contact One Planet.

Climate shell

This shows how the ETFE-coated shell of the climate greenhouse can be opened in the summer to keep the building cool. In the winter the shell is closed to keep in the passive heat of the sun. These adjustable panels and the control mechanism come directly from Dutch industrial horticulture. This is not an expensive architecture or technology, but a practical industrial solution. With natural cooling and heating, and electricity from the 1800m2 of solar panels to drive the heat pumps, it is not necessary to use any fossil fuel to climate control the building. The use of wind and sun for cooling and heating makes the footprint of this building almost negligible compared with traditional buildings.

East view

In Scandinavia, tall office and apartment buildings and bridges have been built of laminated prefab wood; so why not in the Netherlands? Here you see the wooden boxes on the east side of Business Garden, which connect the climate shell with the building. The inside of the boxes is used for extra office space; the top is used for gardens and meeting places. The WWF considers wood to be a carbon sink, while concrete and brick are causes of enormous CO2 emissions. That is why we use wood and recycled materials to renovate the building.

Office as green oasis

Work, live and meet in the most spectacular and ambitious renovation project in the Netherlands ...

A building in a greenhouse

 Build a climate greenhouse over an old building. Add 1800 m2 solar panels on the roof of the greenhouse. The facades and roofs of the old building are packed in a thick layer of cork and plants. Collect rainwater from the big greenhouse roof for the plants and toilets. Light-weighted hotel rooms and meeting rooms hang from the frame of the greenhouse, accessible via a sky bridge. Sustainability goes hand-in-hand with innovation ...

Ground floor bursting with life!

 Terraces in the sun. Protected gardens behind glass. A cozy cafe and restaurant. Space for inspiring exhibitions in view of station square. Meet, live and work in Business Garden ... the bustling ground floor has it all.


  • Renovate an old building with the worst energy label G, into a leading-edge climate-neutral project label A ++ with a market-based business case. If it succeeds here, it can succeed with other discarded buildings.
  • Rent out inspiring, multifunctional, flexible spaces for working, meeting and living. This renovation shows how old buildings can gain a new and long lease of life on a tiny fraction of the CO2 emissions and environmental impact of a new building.
  • Build a national icon of sustainability and 'a pearl for Amersfoort' on Stationsplein.

Status - waiting

In February 2017,  the municipality of Amersfoort purchased the building from the government with the idea of selling it on the open market in 2018-19 under condition that the new owner redevelops it with high sustainability and inspiring architecture. Interested buyers can approach the municipality. The municipality has already approved the Business Garden plan; parties that wish to make use of our experience may contact One Planet.