Systems That Plumb Into Homes
If you’re looking for an RHS that will allow you to use the water to flush the toilet, wash clothes in the washing machine and even clean the house, as well as water the garden, and you’re prepared to excavate your garden, one of your best options is a Graf system, says Phil Barnard, from rainwater harvesting systems supplier Chandlers Building Supplies. “The tank has a self-cleaning filter that you only need to check on it once a year. It costs about $3,000 for a 2,700 liter tank, and a buried tank isn’t affected by heat change or light, so the water doesn’t go green and smelly.”
You should expect to pay no more than $1,500 for installation by a competent plumber or builder, and according to Chandlers no crane is required. The size of tank you should get varies according how much rainfall you usually get, and what you are planning to use the rainwater for. You’ll need energy to pump the water up out of the tank and around the house: this costs about $7 a week for a three-bedroom house using rainwater for ta toilet, washing machine and the garden, according to the RHA – but it does make the system as a whole less environmentally friendly.
The alternative, the Iiter rainwater harvesting system, is a gravity fed and installed in the loft. It collects water direct from the roof by substituting a drain for four roof panels and requires no electricity whatsoever, and costs $1,900 in total to buy and install.” It’s a very simple system and because of its simplicity it means the likes of a competent DIY-er can fit it themselves,” says designer Clive Hall. The internal fitting means that the size of the tank is limited to 455 liters – so in the summer, if it doesn’t rain for a long period, you may have to rely on your mains water system (which will automatically come into play in this situation).
The system is designed to be retro-fitted to existing homes and the maintenance required is low, although Hall does recommend putting a chlorine tablet in the tank before you go on holiday as the tank can start to smell when the water inside is stagnant. The benefits of the system, however, can be huge: “You’ll reduce your water usage by 35% to 40%,” says Hall. “In a rainy season, you can save as much as 55%.”