Rain it in Article from Installers Magazine:
Submitted by admin on Fri, 23/09/2011 - 3:17pm

 

S

Sales of rainwater harvesting systems in the UK have grown rapidly with market volume increasing by almost 850 per cent  in the last 5 years (source: MTW research 2010). There are two principle reasons. Firstly, a need to reduce  our reliance on mains water and consume less than half the amount  we do currently. Secondly, a recognition of the role that rainwater systems can play in reducing risk of flooding by storing the water from roof areas in large tanks. The collected  rainwater can be used to flush loos, wash clothes, clean vehicles or water gardens. Installing a rainwater harvesting system  is relatively simple, but it requires various skilled trades  at different stages of a build

 

Installation process

 

Initially, the builder or civil contractor excavates a hole for the system’s underground tank and its requisite pipework, backfilling as necessary.  The plumber then connects the internal plumbing  and, for gravity systems, connects the tank to a header  tank. An electrician  connects the wiring of the control panel and the pump before the system  is

finally commissioned.

 

As long as manufacturer guidelines and regulations are adhered to, there should not be issues with any part of the installation, commissioning, or safe working of a system.

 

 

 

Tips  to ensure effective installation Designing the system. Bringing in the company supplying  the system  at the beginning of the project planning  will allow them to create  a specified, pre-designed system that includes  sizing the system and storage  tank in accordance with BS 8515 and the Code.

 

 

Siting the  tank.  Siting the tank in a garden  rather than under a driveway is more cost effective and practical. A driveway location, by contrast, requires the addition  of a heavy duty access frame and cover to protect  the tank from the vehicle loading.

 

 

 

 

Securing the  tank.  Some manufacturers advise using peagravel to back-fill a tank in dry site conditions. However, a system  which has been installed to reduce  surface water

run-off is likely to be sited on impervious soil. If the tank is surrounded by peagravel, surface water will filter down around the tank creating  a buoyancy issue. The problem can be avoided by using a concrete backfill under these types of conditions. You can protect  the tank against dirt ingress  by covering its neck with plastic during the installation.

 

 

 

Compliance with water fitting regulations. Installing rainwater harvesting equipment brings with it new levels of Water Regulations requirements which are vital to protect the public water supply.

Many of the regulations revolve around three principle requirements for rainwater harvesting equipment to comply with:

 

1       Marking and colour coding of the plumbing  to ensure  that pipes carrying rainwater are not connected into in future to satisfy potable water requirements. Rainwater  harvesting pipes are black with green  stripes  – which are now available through  merchants while potable water pipes are blue. The pipework must also be labelled every 500 metres  internally and

a Type AA or AB air gap in the system  is required to avoid any contamination of mains water supplies.

 

2      If a system  incorporates a back-up supply from the public mains e.g. a gravity system, then a plumber must notify their Local Water Authority. The minimum are a site plan, a schematic drawing  of the plumbing  layout and details of what is proposed. The local Water Authority must inspect at first fix and second  fix stages.

requirements

 

 

Connecting pipework. Following the manufacturer’s guidelines  will to avoid the misconnection of the outlet pipes on the tank to the pump, a situation that will render it operational, but not pumping  water.



 

 

Locating the  control panels. It pays to make an early decision on the location of the control panels for the rainwater system.  Houses built to Code Level 5 or 6 are likely

to have a number  of energy-or water-saving technologies installed, including air source/ ground source heat pumps  or solar panels, all of which have control panels which will have to be accommodated.

 

 

 

»

DOWNLOADS