How to collect rainwater at home

Don't let bad weather rain on your parade, learn the full process of rainwater harvesting and follow our steps to try it at home.

Updated September 5, 2019

green rainwater tank in garden

Key steps:

To collect rainwater from your home, follow these key steps: 

  1. Decide on which rainwater collection method you want to use.
  2. Collect all the necessary resources if choosing a DIY option. Speak to experts for advice.
  3. Check with local authorities to ensure collecting rainwater is legal where you live.

Collecting rainwater for your home and garden is a fantastic way to save money, especially if you live in an area with frequent rainfalls. It is also useful for conserving water since you can use rainwater for most of your households needs. Here we explain how to collect rainwater at home, including setting up your own process of rainwater harvesting.

Be sure to keep your water tank clean by rinsing it out every few weeks and getting rid of any sources of bacteria. 

What is rainwater harvesting? 

If you’re wondering how rainwater harvesting works, it can be tricky to know where to start.

Here are the basics that you need to know: 

  • Rainwater harvesting is the process of collecting and sometimes storing water that has fallen as rain for use around the house. 
  • It is a way of making use of the water that would otherwise go into the gutters and drains around your home.
  • There are lots of potential uses for collected rainwater, including watering the garden and washing your car. 
  • Many people advocate rainwater harvesting as a way to reduce their water consumption and live a more sustainable life. 

How to collect rainwater from a roof

There are many different ways to collect rainwater but one of the more common is to set up a system that collects water as it runs from the roof. There are a range of options for this but one of the best methods of rainwater harvesting is to go DIY.

  1. Get a water tank - make sure it is of sturdy quality and a suitable size for your needs and expected rainfall.
  2. Place the water tank underneath your down spout. This should be part of your roof's existing guttering.
  3. If making your own water tank, make sure it is water-tight at the spout to avoid wasting water. You should also add a fine mesh fabric to the top of the water tank to keep pests out of the water.

How to collect rainwater without a roof

While roof collection may be the easiest option of rainwater harvesting, there are a few other ways to go:

  • Dig a hole in your garden and line with tarp to collect water quickly and easily. As this water may be more exposed to pests and bacteria than other sources, you should not use it for cooking, drinking, or personal hygiene.
  • Clear an area of elevated ground in your garden and cover with tarp. Secure the tarp with stones and run a hose pipe from the bottom corner of the tarp to a collection tank on lower-level ground in your garden.

How to collect and purify rainwater 

Of course, you might have a lot of water that has fallen as rain but there are only so many things you can do with it in this state. Rain water can have nasty bugs and bacteria so it’s definitely not suitable for drinking - at least not without purification. 

To purify rain water, you can use one of three main options:

  • Filtering - using mechanical tools or substances such as charcoal or sand to remove contaminants from the water.
  • Tablets - shop-bought remedies that help to neutralise substances in natural water.
  • Boiling - heating the water to boiling point and then using distillation equipment to collect the cleaned water and leave any sediment behind.

Read our dedicated article on how to purify water for more guidance on this.

Sound like hard work? Use untreated rainwater for the following purposes around the home instead:

  • Watering plants
  • Plumbing needs - such as flushing toilets
  • Washing cars, outdoor areas, and other vehicles
  • Other non-drinking purposes

Remember: there may be local laws around collecting rain water so be sure to check with your local authority before you start and ensure whatever rainwater collection method you choose is legal.

If one of your motivations for rainwater harvesting is to preserve water then there are lots of other techniques you can try. Check out our article on ways to save water at home for more guidance.

Originally published August 29, 2019