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Sponge City Mats

Water absorbing mats to keep rainwater in the city for better heat, flood and energy management.

Photo of Jurijs Kovzels
23 19

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Sponge City Mats is a way to retrofit existing rooftops to facilitate natural evaporative cooling effect. Sponge City Mats absorb and keep rainwater imitating natural environment where water is soaked up by soil and vegetation.

We all experienced how cities can be scorching hot at summer, becoming much warmer then surrounding rural areas. This phenomenon occurs in part due to unnatural way how cities manage rainwater.

In the nature, rainwater is absorbed by soil and vegetation, and when temperature rises, water evaporates producing natural cooling effect.

Unlike in natural environments, rainwater in the cities is historically dumped into pipes and drainage system breaking natural cycle and cooling.

Sponge mats are aimed to restore natural processes by absorbing rainwater and allowing it to evaporate when temperature raises.

Sponge mats is the viable alternative to reflective white roofs and green roofs.

White roofs are found to be effective in reflecting sunlight and cool down the surface of the roof. Sponge mats when painted with reflective white coating provide the same benefits, and besides that, leverage evaporative cooling effect.  

Green roofs, roofs with soil and vegetation, provide benefits of natural cooling but entails high installation and maintenance cost and can be inefficient in water deprived regions.

Sponge mats leverage benefits of both white and green roofs and is cost-efficient and low-maintenance solution.  

Sponge mats are produced of 99% percent on recycled Nike Grind materials.
Sponge mats leverages inherent properties on Nike Grind materials to absorb and keep water and requires close to zero energy consumption to build.

Website (if applicable)

Which Nike Grind materials will your idea utilize?

  • Rubber Flashings
  • EVA Foam Injection Scraps
  • EVA Foam Flashings
  • EVA Foam Components
  • Laminated EVA Foam
  • Laminated PU Foam
  • Mixed Footwear Textile
  • Split Leather Scraps Coated

How specifically will these materials be incorporated into your solution?

The Mat consists of 2 main layers: absorption and isolation layers. Spongy absorbing layer, composed of the mix of Nige Grind materials. Composition of the materials and methods to fasted or clue the grind will be determined experimentally to achieve best absorbing and evaporating properties. Thin liquid rubber waterproof isolation layer covering the mat all sided except the top to form a container holding rainwater. This layer is optional. In the long run melted foam and rubber Nike Grind materials can be used fasten the component of Absorbing layer and to form outer isolation layer. This will make the entire production of the mats use only recycled materials.

What is the current stage of development of your idea?

  • Research & Early Testing

Describe your target market. Who will benefit from your product?

Primary application: 1. Factories, warehouses, or any number businesses operating from flat roof buildings and spending money on air conditioning of premises. 2. Residential communities making building more energy efficient and improving living conditions. 3. Walkable modification can be used in public spaces and on playgrounds. Alternative applications: 1. Sealed in fabric can be used to alter soil mechanics in landscaping and agriculture 2. Office workers when used as acoustic panels

How will you scale your idea? Please describe in detail your plan to scale your concept.

Berlin is the optimal places to start and scale business like Sponge Mats. Germans are ecologically conscious and willing to make sacrifices in the name of energy independence and climate protection. Business are pushed to improve energy efficiency due to the costs and governmental requirements. Thriving social entrepreneurship startup scene. We will seek partnerships with local businesses through governmental organizations and social impact communities. We will also reach and work together with city architects to improve the design and incorporate the mats into upcoming city improvement projects. The core concept of the mats has multiple applications and allows leeway to adjust and pivot the business model. The biggest challenge to deliver the product to market is navigation of German fire safety and construction regulations with can be tricky and time consuming. To mitigate this challenge, we will start dialog with authorities at the early stage of the project development.

How is your idea innovative?

Sponge Mats utilize recycled materials in the new way allowing to imitate natural process making city ecosystem better for living and more environmentally friendly.

What inspired this idea?

Idea of Sponge City is nothing new. Berlin's suburb Rummelsburg, build 20 years ago, is an example of this concept. The problem is that it is not feasible to rebuild existing cities to handle water more naturally. Sponge City Mats can help retrofit some existing building and city surfaces.

Tell us about yourself and your team. What is your background and experience?

Jurijs is Service Designer with entrepreneurial experience. Jurijs is interested urban development, mobility, and sustainability. Mariia is Marketing Expert with Business administration and economics education and experience in B2B sales.

In what city are you located?


In what country are you located?


Please describe how becoming a Top Idea will support the growth of your concept.

Funds will allow as develop and deploy first prototypes for testing and iterate on the design. Part of the funds will be used to test different marketing channels and developing marketing materials.


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