11 Sep 2017
Green infrastructure offers climate resilience in urban environments.

How vegetated roofs alleviate impact of climate change

Vegetated roofs, otherwise known as green roofs, are a key part of infrastructure resilience in an era of extreme heat events and more frequent and intense downpours.

Below are 4 ways vegetated roofs can have an immediate impact to improve resilience:

 

1. Help manage localized flooding

Vegetated roofs absorb rainfall, and help prevent water from overwhelming stormwater sewers and flooding streets or basements.  This reduces damage to infrastructure and property. They also reduce the volume of stormwater that flows into streams and rivers and thus protect local watersheds.

 

Vegetated roofs help mitigate urban heat island effect cooling the building, surrounding air and improving human health and comfort.

Vegetated roofs help mitigate urban heat island effect cooling the building, surrounding air and improving human health and comfort.

2. Help reduce urban heat island 

Vegetated roofs are a natural cover for rooftops that would otherwise absorb and retain heat.  Vegetated roofs mitigates air pollution levels an remove heat from the air through evapotranspiration. On hot days, vegetated roofs, reduce temperatures of the roof surface, and the surrounding air, improving human health and comfort.

 

 

Vegetated roof reduces the heat flux through the roof.

Vegetated roof reduces the heat flux through the roof.

3. Help lower building energy demands 

By shading the surface of the building, the vegetated roof is reducing the heat flux through the roof and reducing the indoor temperatures and demands on air conditioning.

 

 

 

 

Vegetated roofs delay peak flow and reduce pumping and treatment demands for municipalities.

Vegetated roofs delay peak flow and reduce pumping and treatment demands for municipalities.

4. Help save money managing water

Vegetated roofs retain and detain rainwater, delaying peak flow into sewer systems which helps reduce pumping and treatment demands for municipalities.

 

01 Feb 2017

The most notable development to date in vegetated roofing is the production of the needled mineral hydro blanket – a non-petroleum and formaldehyde-free alternative.

Knauf’s innovative needling manufacturing process provides dimensional stability without use of chemical binders.  The needled hydro blanket is formed by mechanical interconnection of pure mineral fibers.Needled Mineral Hydro Blanket

This process forms a structurally stable, lightweight and porous material with longer fibers that maintains excellent water holding properties. It is consistently hydrophilic, even after various weather cycles throughout the year. Up to 90% of the material retains rainwater. When wet, the majority of the retained water is easily available for the plants uptake.

The water absorption characteristics are not affected over time as nothing rinses away and will remain the same throughout the lifetime of the products.

The Needled Mineral Hydro Blanket is ideal for vegetated roofs, as it:

  • can supplement, or in some cases replace, heavy growing media
  • can act as a water reservoir and support plant health
  • achieves greater LEED credits
  • performs exceptionally and reliably as a rooftop stormwater management tool over the lifespan of the vegetated roof

Needled Mineral Hydro Cubes and Hydro Flocks

hydro cubesThe above needled, binderless, mineral wool also comes in the form of small hydro cubes (about 0.7 cubed) or hydro flocks (0.1-0.7 inch pieces) to mix with traditional growing media.

This is an innovative method of  improveing traditional growing media. Cubes and flocks contribute to better soil structure, water holding capacity and aeration of growing media. The retained rainwater inside the hydro cubes or hydro flocks is easily available for plant uptake, improving plant survivability. Cubes and flocks are specially recommended for patios, terraces and home gardening.