Polder roofs

Polder Roofs have an increased capacity of water storage, retention and drainage. Therefore the Polder Roof is the ideal foundation for green roofs, roof gardens and green roof parks.

Why a Polder Roof?

Due to the excessive amount of paved surfaces in cities, high pressure on the sewage system is inevitable during heavy rainfall. Additionally, climate-change will ensure more rainfall and will cause this pressure to increase. The Polder roof offers a solution to this problem by functioning as dynamic water storage. In this way, a large part of the paved city can be transformed into a green, water absorbent solutions to flooding. In order to create a rainproof city, there will need to be invested in the public space (garden to rooftop). Rainwater can be collected and reused.

Rainwater is a resource, not waste.

What is a Polder Roof?

The Polder roof is made up of a system of crates that can store rainwater. The basin that comes into existence can be dynamically controlled. In this way the Polder roof is capable to store all the rainwater and drain it at a later preferred time. This is how we can prevent water flooding the city. The Polder roof also serves as a foundation for the upper layer such as a green rooftop, roof garden or roof park. In return, the stored rainwater can be used for irrigation.

Polderdaken Opbouw Dakdokters Amsterdam

How does it work?

The requirements of the client, the demands of the water manager and the bearing capacity of the roof determine the ability of the water storage capacity. The maximum water buffer is 135 mm per m2. The hardware does not change, only the settings are adjusted. Performances of the Polder roof can be monitored online and when necessary the system can be regulated from a distance. In the end a network of Polder roofs is created which contributes substantively to the city’s water management.

Polderdaken Groendak Dakterras Daktuin Dakdokters

Water storage

  • Maximum of 135 mm water buffer
  • Intercepts 100% of all the rainfall
  • Perfect foundation for multifunctional rooftops.
Polderdaken Groendak Dakterras Daktuin Dakdokters

Controlled water level

  • Dynamic control of water drainage
  • Safety setups for storage and frost: 100% safe
  • Entirely powered by solar energy
Polderdaken Groendak Dakterras Daktuin Dakdokters


  • Real-time information about rainfall, storage and drainage
  • Historical database
Polderdaken Groendak Dakterras Daktuin Dakdokters

Remote controlled

  • Login online
  • Management of rainwater at neighborhood level
  • Adapting to and administering situations