Brian's House Building Blog

An Easy Guide To Planning The Perfect Rainwater Harvesting System

by Peyton Sanders

People are facing growing concern about finite water resources and how they can conserve and use water more responsibly. Capturing rainwater is one simple method that has been used over the centuries. It is well within every householder's capability today. Perhaps you are keen to harvest one of nature's finest resources to help reduce your escalating water bills. After all it's free! This advice will provide you with the necessary background information and know-how you need to go about harvesting rainwater. Although at first it appears very straightforward, this handy cheat sheet will point out the things that are not immediately apparent.

Basics Of Rainwater Harvesting Systems

The system relies on a perfectly simple concept: collecting water from the roof and gutter system of your home and conveying it to a storage tank. Your system can be designed to suit your needs, ranging from high level use as a main household supply to the small and occasional back-up water source. Either way, it is always good to make a start with the most undemanding task.

Choose Your Tank Type

With the need to accommodate today's smaller properties, compact, slim-line rain water tanks are now the norm. Designed to be installed along fence lines or in tight spaces, they are attractive space savers. The polyethylene material is extremely robust, lightweight and comes in a huge range of styles and colors that will blend with any style of home.

Decide On Usage

The way you propose to use the water will influence the design and maintenance required. Harvested water is ideal for many purposes around the house, from watering the lawn and garden to washing, cooking and cleaning. Drinking rainwater provides a pleasant, fresh taste completely free from chemicals. While water can be collected from any roofing material (aside from asbestos), to harvest water of suitable quality for drinking, you need to avoid collecting from:

  • Any section of roofing that contains lead flashing or asbestos sheets
  • Roofs painted prior to 1997, before lead levels in paint were removed entirely
  • Roofs exposed to environmental pollutants such as nearby chemical processing plants and industry smokestacks.

Unsurprisingly, your roof and gutters also need to be in good health before your system can operate effectively.

Prepare By Checking Your Roof System

If you are not up for climbing around on the roof and would rather avoid working anywhere above solid ground, then don't think twice about arranging for some professional assistance. An experienced roofing and gutter repairs company will do a quick inspection to see if everything is in order. When all is ready to go, use this convenient checklist to ensure that you have everything necessary to have an effective system. If you are leaving the job to the professionals, use the list to monitor their progress and be fully aware of what should be happening at every step.

Roof and Gutter Work

  • Have all gutters repaired
  • Make sure you have gutter mesh installed to prevent leaves and other debris from collecting in your gutters
  • Have gutter outlets fitted from underneath the gutter to avoid any obstructions to water flow
  • Install insect-proof flap valves or screens to the end of all pipes
  • Ensure that rain heads with filters are fitted over the downpipes to prevent mosquitoes from breeding in the pipes and stop blockages from debris
  • Check that a first flush diverter is installed as it helps prevent contaminated water from entering your tank. This diverts to first flow of rain water as is likely to contain dust and debris that has gathered on the roof.

Tank Fitting

  • Have a tank screen fitted at the entry point to the tank also to protect from insects
  • Fit an air gap to the tank overflow outlets to avoid storm water back flowing into the tank
  • Monitor your water usage by fitting a gauge to show the water level in the tank

Collecting rainwater from a well-designed, well-maintained system will not only save you money on your ever increasing water bills. You can make an important conservation contribution by becoming less dependent on mains water and reducing the amount of damaging storm water run-off to the environment.