How To Make Your Own Rain Barrel Watering System

I don’t need to remind you just how precious and scarce the wet stuff is to all life on this planet. We need water for absolutely everything. Consider your morning routine for a moment. You wake, use the toilet, make a coffee, take a shower – what would your day be like if any single one of those things was missing, due to a lack of water.


We are lucky for the most part that many of us still have plenty of water every time we open the faucet, in fact we should admit that we generally feel complacent about it.

Yes we know that drought is increasingly prevalent across the world, and it’s true that there are warmer temperatures the year round. But the planet has plenty of water right?

Well not exactly. The majority of the water that we use – for everything from flushing the toilet to watering the garden is purified drinking water. Come on, that is crazy right?

There is no denying that this is wasteful.

Ancient humans gathered and stored rain water for their needs, so maybe it is time for us to step back in time and follow their wisdom. Rain water is considered to be ‘grey water’ so it is not suitable for human consumption. Further treatment is required to purify it before we can drink rain water.

But what about your other water needs?

Watering the garden for one thing is a fantastic way to use rain water and save the drinking water that we need to conserve. Plants love rain water, for it’s softness as well as for the fact that it contains fewer chemicals including chlorine.

Rain water can help to stabilise the pH levels in the soil, and you may find that you require far less fertiliser to boost the growth of plants compared to using normal tap water.

Don’t forget that you will also save money on your water bill by using rain water rather than your municipal water to water the garden. Building your own rain barrel watering system is surprisingly simple, cheaper than you might expect and once it is in place it is virtually maintenance free. If you follow the tips below gravity will do the hard work for you, and you can relax in the knowledge that your garden will be beautifully watered without wastage.


How Much Water Can You Gather?

You might be surprised just how much water you are able to collect from normal rainfall. Even in light rain you will be able to catch several hundred gallons of roof run-off.

The calculation to know is 1 inch of rain on a 1,000 sq foot roof will equate to 600 gallons in your system!

With this in mind, you will need to use only strong and sturdy barrels. With water weighing something like 8 lbs per gallon, it will be supporting somewhere around 400 lbs of water when full!


If you are curious about how much rainfall your roof might capture, check out this handy calculator.

What Do You Need To Build Your Own System?

A rain barrel watering system comprises 3 main components.

  • Collection
  • Storage
  • Output


To collect the rain water effectively you simply need a wide surface and a piping system. In most cases this simply means your roof, gutters and down-spout.

Gutters are essential, and if your house doesn’t have these then this will be the biggest investment, but it is a once off cost (as long as the gutters last – which should be a long time!).

Don’t be tempted to skip the down-spout though – as any direct concentrated flow of water off of the roof can cause damage to the house foundations over time. Don’t simple let water be directed from the gutter into the barrel from a distance. Use a down spout to protect your home.shutterstock_197315396


You have a number of options when it comes to the storage tank that you decide to use. One thing to remember is to avoid square barrels like the plague! To be honest it is not clear why these are even made, when they constantly split, crack, and leak at the corners.

You can purchase a manufactured system, with barrels at around $85-135 each for a 55 gallon container. With that everything is done for you – although I have seen a few bad reviews about the standard fittings that come with these.

For the purposes of this post we are assuming that you are a hands-on, non money wasting, DIY type of person. So we are going to tell you how you can get a barrel for nothing – or almost nothing at least!

Many food and soft drink manufacturers have a load of 55 gallon barrels that they need taken off their hands. They can be used only once in most instances in their production, and it is costly to dispose of them correctly – so step in and help!

You are looking for food quality barrels, 55 gallons. The kind that have stored only food stuffs – and absolutely nothing toxic. Stating the obvious I know.

You can also buy food quality barrels from your local hardware store for around $20, and they come in all shapes/colors/sizes – avoid square remember!

Screw Top vs Sealed Barrels?

There is divide opinion over this question. The benefits of using a screw top barrel are that you can gain easy access inside to add the plumbing, and also to remove leaves.

However, sealed top barrels are more abundant. You don’t really need full access inside for the fittings and leaves can be avoided by used a debris gutter and down spout screen.

You consider getting a debris screen and lid for the barrel if you are opting for an open topped barrel. This will prevent mosquitos from breeding (huge bonus) but is also a safety precaution, stopping small animals and curious children from coming into any danger.

It is advisable to get your barrels delivered unless you have a decent amount of space, they are not going to fit into a regular car!

Where To Position The Containers

When choosing the location for your barrels you need to consider a few things. Firstly, it makes sense to position them against a wall – obviously this will mean they are close to the gutter which is a bonus, but also it will prevent them getting in the way of foot traffic. You don’t want any chance of a water barrel being knocked over and dislodged – a full water barrel could easily crush a child, animal or even an adult.

Consider plants that currently depend on the runoff, they may be enjoying their position beside the house where they get to enjoy all the rain water. Maybe repositioning these could be the answer.

As we have mentioned, the barrels will fill up quickly and then become extremely heavy – so moving them around will not be a realistic option. Choose your spot carefully.

If you are worried that your containers will be an eye sore to which your neighbours or spouse may complain, then remember you can paint them in primer that will stick to plastic. A color that matches your walls is ideal – they will be almost invisible.shutterstock_228783478


So collecting the water is just half of the system, you also need to get the water out and where you want it to be. Stooping into the barrel with a watering can will get old very quickly. Rather let gravity do the work for you. And for this you will need to elevate the barrels.

You can build your own sturdy stand for this, using salvage timber to save money.  Dig the posts deep and cement in place – making sure that the surface is completely level. You can go ahead and paint this in a color to match the barrels! Alternatively you can use cinder bricks to elevate the collection tanks.

The distribution device will generally consist of a spigot, hose and an on-off valve, although you can tweak this to suit your own needs. The following tutorial explains exactly how to set up your own system.



Setting Up The Rain Water Collection / Distribution System

This is where it gets a bit technical! You can follow the awesome step by step instructions provided by the fantastic, you are just 15 steps away!

The Spigot & Hardware

You’ll need a ¾” hose bib spigot (½” will work too but with smaller locknut and washer). These have male threads at one end to screw into the barrel and at the other to attach a standard size hose. You’ll also need a ¾” galvanized locknut (McLendon’s has these), a rubber washer with a 1″ inner diameter, Teflon tape, super-glue and silicone.

The Overflow Valve & Hardware

You’ll need a ¾” brass overflow valve which, like the spigot, has male threads on either end with the outer end able to connect with the female end of a hose (plastic will work too). These are called “male hose MIP adapter ¾ x ¾ x ½” at Lowe’s and #A-665 at Home Depot. You’ll also need the locknut, rubber washer, Teflon tape, super glue, and silicone.


  • Electric Drill
  • 1″ hole saw or drill bit (use 15/16″ for very secure fit)
  • Utility knife
  • Needle nose pliers or wrench
  • Vegetable oil and cloth
  • Screw driver and ½” dozen screws (see #14)
  • Mesh-screen for top filter 
  1. Clean and rinse your food clean container with a mild soap and water (rainwater if you’ve got any yet)
  2. Drill a 1″ hole with your hole saw or drill bit, just off the bottom of the container for the spigot assembly. I put mine as low as possible to maximise easy water use. It’s designed to be used with a stand. I use four cinder blocks. Note: If you are unable to reach down to the inside bottom of the barrel, you might want to use a 15/16″ bit and put the washer on the outside of the barrel.
  3. Drill a 1″ hole an inch or so below the rim for your overflow valve assembly. This hole can go anywhere around the barrel at that latitude. Keep in mind: don’t put it too close to the top (overflow) or too low (lose water storage). I recommend you put the hole an inch/inch ½” from the lid. Please note: if you’ve got a 2,000 square feet roof and those large down spouts, you may want to get a larger overflow valve.
  4. Use that 1″ bit to drill a dozen or so holes in the lid. Rainwater will filter through mesh-screen then through holes into barrel.
  5. Take utility knife to clean scraps around holes.
  6. Wrap the barrel end of the spigot three times around with Teflon tape and then screw in the spigot squarely. It should go by hand.
  7. Take the rubber washer and glue the surface of one side with a strong glue and reach into the barrel and work it over the threads. Flush with the barrel.
  8. Screw on the locknut and finish tightening by turning the spigot while holding the locknut with a wrench or needle nose pliers. You may need a second person to turn while you hold or vice versa). Authors note: I love needle nose pliers!
  9. Wrap the longer end of the overflow valve with Teflon tape three times and then screw it into the overflow hole by hand or by using a wrench or pliers if necessary. The outside male threads should be able to connect with a standard size hose to divert the overflow.
  10. Repeat #7
  11. Screw on the locknut as far as possible by hand, then hold locknut while tightening overflow valve with pliers/wrench until it flies out of your hand or is very tight.
  12. Take a tube of all-purpose silicone “goop” and apply a bead where overflow valve meets the outside of the barrel. Note: I do this as an added sealant. It may not even be necessary.
  13. Take a tube of all-purpose silicone “goop” and apply where the spigot meets the barrel. Follow drying time directions from the silicone tube.
  14. Trace the outline of the lid on a mesh fibreglass screen and then cut it out. Screw on, if necessary, or just tighten ring around cap to secure. This screen is designed to keep mosquitoes out.
  15. Finally, take a rag and some cheap vegetable oil, and apply it to the scratched areas of the barrel. It really shines it up.


So there you have it, this is how to make your own rain barrel watering system. It is certainly a project that could be completed in a weekend. And once set up, it should be almost maintenance free.

The whole thing is pretty simple and low cost but leads to long term returns. You can feel good that you are taking a weight off of the municipality, while reducing your own bills and even adding value to your home.

One thing to mention before you get started in that you should check it is legal in your area to harvest rainwater. I know it sounds absurd, but in some areas you could be prosecuted.

We would love to hear from you if you are planning to set up your own system, or maybe you already do this at home. Please share your own tips and tricks below!

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