Polypipe – one of Europe's leading manufacturers of
piping, water and climate management systems – has won a Green Apple
Environment Award in the annual international campaign by the Green
Organisation to recognise, reward and promote environmental best practice.
In the awards, Polypipe was recognised as a Green
Champion for Environmental Best Practice. The award is for a group research
project into ‘smart roofs’ and utilising the installation of a blue-green roof
at group company Polypipe Terrain’s plant in Aylesford, Kent, to explore new,
intelligent water management systems.
The award
was presented oat a House of Commons event hosted by Green Organisation
Managing Director Roger Wolens.
The Smart Roof 2.1 research project has been
underway since 2017, and aims to determine the hydrological, thermal and
biodiverse functioning of blue-green roof systems in the urban
environment.
A prime
goal is to harvest and store as much rainwater for capillary plant irrigation
as possible and only use potable water in the case of extreme or prolonged
droughts. The greening outcome is that the system has a higher urban cooling
capacity, reduces rainwater discharge run off rates to sewers and enables a
wider species selection due to improved water availability.
Polypipe’s
deep understanding of the water management challenges cities face – along with
those of providing sustainable soft urban landscaping – meant the decision to
install a blue-green roof when re-roofing its Aylesford plant was an easy one,
especially as it also wanted to demonstrate the viability of retrofit green
infrastructure.
Not only
did the blue-green roof encourage biodiversity and prove a valued leisure space
for employees; the intelligent water management system optimised greening,
increased water usage efficiency and reduced waste, and managed extreme weather
events.
The system
comprised a drainage sub-base replacement with sedum top layer and an isolated
instrumentation cell to automatically monitor and manage water supply to ensure
optimum soil moisture, temperature and salinity conditions, allowing the green
roof to flourish. The control and monitoring systems are operated remotely
online via a smartphone, tablet, or PC.
In
brief, capillary cones – unique to the sub-base platform – draw stored
rainwater upwards to irrigate the green roof, while sensors within the cells
monitor available water levels. If a pre-determined ‘low set-point’ is reached,
the system operates a solenoid valve to add water from a rainwater recovery
tank until the desirable level is reached. During high-rainfall events, excess
water in the wet cell spills into the raft. When the tank reaches capacity,
this water overflows to the drain.
The
results of this smart management of water collection were demonstrable,
positive and obvious, and included: higher diversity in both plant and insect
species; reduced average annual water shortages for sedum-dominated vegetation;
increased evaporation reducing run off and waste water discharge to ground
systems and increased building cooling capacity.
A second
research project based around the Polypipe blue-green roof will consider the
use of stored water for business usage, such as WCs; cooling solar panels and
thus improving outputs; and its insulatory effect in winter.
