If you have a garden or other open space, it is possible to set up a rain barrel. This catches rainwater, which you can use in a variety of ways. For example, you could water your plants or do other gardening work with it. With a little effort, it is even possible to wash your clothes with rainwater to save drinking water.
In our rain barrel test 2021 we introduce you to different types of rain barrels. Basically, you can distinguish them by their material. For example, there are rain barrels made of wood or plastic. We therefore show you the individual advantages and disadvantages of each type of material.
Furthermore, you will find a lot of useful information about rain barrels, possible uses, the perfect location and much more in this article. We also present some of our top favourites.
- 1 Weekly newsletter with the best personal finance tips
- 2 Summary
- 3 The Best Rain Barrel: Our Choices
- 4 Guide: Questions you should ask yourself before buying a rain barrel
- 4.1 What is a rain barrel?
- 4.2 Can I use rainwater for household purposes?
- 4.3 Which size is suitable for which user?
- 4.4 Can I work out what size my rain barrel should be?
- 4.5 What is the perfect location for a rain barrel?
- 4.6 What does a rain barrel cost?
- 4.7 What are the alternatives to a rain barrel?
- 5 Decision: What types of rain barrels are there and which is the right one for you?
- 5.1 What distinguishes a plastic rain barrel and what are its advantages and disadvantages?
- 5.2 What distinguishes a wooden rain barrel and what are its advantages and disadvantages?
- 5.3 What are the characteristics of a metal rain barrel and what are its advantages and disadvantages?
- 5.4 What are the characteristics of a stone rain barrel and what are its advantages and disadvantages?
- 5.5 What distinguishes an amphora-style rain barrel and what are its advantages and disadvantages?
- 6 Buying criteria: You can use these factors to compare and evaluate rain barrels
- 7 Facts worth knowing about rain barrels
- A rain barrel is not only a useful garden tool, but can also be used as a decorative object.
- When buying a rain barrel, you don't necessarily have to choose a plastic one. Wooden, metal and clay bins are also available.
- You should choose the capacity and dimensions of the rain barrel according to the size of your garden.
The Best Rain Barrel: Our Choices
Guide: Questions you should ask yourself before buying a rain barrel
What is a rain barrel?
On the one hand, this saves you water costs, but it is also easier on the environment. How exactly you can reuse rainwater is explained in the following sections.
Can I use rainwater for household purposes?
If you have any questions about the necessary installations, a specialist will be happy to help you. In any case, you have to report it to your water supplier and must not dispose of the rainwater with the tap water without asking.
The discharge into the sewage system must be clarified in advance. Under certain circumstances, however, you may even receive a subsidy.
Formula for calculating demand in the household
Please bear in mind that the amount of rainwater harvesting depends on the weather and is subject to certain fluctuations. A water supply for the household exclusively via rainwater will therefore not be possible.
Number of persons x average daily consumption x number of days of use
Example: 2 x 60 litres x 30 days = 3,600 litres.
Make sure that tap water can be supplied when the water level in your water tank is low and that all pipes are labelled so that you can always see what water is flowing through them.
The separation of drinking water and rainwater pipes is a legal requirement!
Which size is suitable for which user?
If you need a large rain barrel, you can buy an oak barrel with a capacity of 5,000 litres if you have a budget of 2,000 euros or more. If the need is even greater, there is the option of a so-called cistern. This can offer a capacity of 10,000 litres.
Due to its size, a cistern is very heavy and is often buried underground. This also makes them frost-proof and the darkness in the ground prevents algae from forming.
If you are unsure whether a standard cistern is enough for you, then be advised that you don't have to make a permanent decision right away: after all, you can always combine rainwater cisterns of different sizes with an overflow set.
Can I work out what size my rain barrel should be?
- What is the average local rainfall?
- How large is the roof area of your house / garage / tool shed etc. from which you want to collect rainwater?
- How big is your garden / vegetable patch / etc.? - i.e. the area you want to irrigate?
You can find information on the amount of precipitation on various weather maps. When calculating the amount of rainfall, pay attention to whether it is a seasonal value or the annual amount. The values shown give you a good indication of the appropriate size or you can use a rain gauge.
For a better understanding: 1 litre per m² is equivalent to 1 mm water height per m². 300 mm precipitation per square metre = 300 litres of rainwater per square metre.
Theoretically, this amount of water will fit into your rain barrel. Theoretically, because the probability of precipitation also plays a role.
And also the fact that - depending on the type of roof tile - not every drop of rain will actually make it into your rainwater butt. You can find the correct calculation value for your type of roof tile on the Internet under the keyword "roof coefficient".
m² roof area x roof coefficient x amount of precipitation per day (precipitation frequency).
Example: 60 m² (roof area) x 0.8 (clay tile) x 4.3 litres = 206.4 litres. With a result like this, you can, for example, draw from the full range when selecting an offer.
However, please consider your actual needs again. If you don't need the water you've collected, it can start to stink if you don't use it for a long time.
What is the perfect location for a rain barrel?
If you have a wooden rain barrel, you must also ensure that it is well ventilated so that the wood does not rot. A layer of gravel under the bottom of the barrel is ideal.
For your comfort during use, it is advisable to place the rain barrel on a stable and tip-proof pedestal. A nice and sensible option is a brick pedestal with a plate on top. This way you can comfortably place your watering can in front of it to fill it up.
Place your barrel near the downpipe of your gutter. This saves you having to lay a complicated pipe system across the garden. If you take all these points into account and have easy access to the watering can and hose connection, you have probably found the perfect place for your barrel.
What does a rain barrel cost?
- Load capacity
You can buy an average rain barrel for 50 to 100 euros. If it is supposed to look particularly pretty and appealing, this is usually reflected in the price. The same applies to the material you choose and your expectations of the workmanship.
If you want to buy a durable product that you will use regularly and enjoy for a long time, do your research. Products that are intended to withstand multiple uses and different environmental influences have their price.
Rainwater cisterns are usually priced in the four-digit range. But if you want to start small, that's no problem. Try a wide-mouth plastic barrel with a screw cap. You can use this as a small mini rain barrel with a capacity of 10 litres. Such products are already available for less than 20 euros.
What are the alternatives to a rain barrel?
Otherwise, there are so-called wall tanks. These also collect rainwater, but, as the name suggests, they are mounted on the wall.
Decision: What types of rain barrels are there and which is the right one for you?
Collecting rainwater is on the one hand a good way to save money and on the other hand a sensible way to deal economically with the resources of our environment. Rainwater evaporates from streams and rivers when it is warm enough and then goes on its way.
When it has travelled a corresponding number of metres in altitude, the rainwater condenses at a cold altitude and makes its way back to earth as drops. In the process, however, it also picks up various pollutants from the air and impurities from roofs and gutters.
Rainwater is therefore not suitable as drinking water for humans. For plants, however, some of these additional ingredients offer many advantages over our hygienically treated drinking water. This is an advantage if you want to water them with rainwater.
Basically, we can distinguish between five different types of rain barrels:
- Plastic rain barrel
- Rain barrel made of wood
- Rainwater tank made of metal
- Rainwater tank made of stone
- Amphorae made of clay or plastic
All types offer different advantages and disadvantages, which are mainly determined by the material used.
What distinguishes a plastic rain barrel and what are its advantages and disadvantages?
It is the classic: the plastic barrel in blue or green. The robust plastic barrel is light in weight and one of the easier-to-clean variants.
You don't need to worry about harmful substances here. If your barrel is made of hard plastic, it already has one thing in common with many drinking water pipes. As the name suggests, plasticisers are released by soft plastic.
What distinguishes a wooden rain barrel and what are its advantages and disadvantages?
Oak wood, larch wood or chestnut wood? Whiskey barrel or rum barrel from Jamaica? There are many possibilities. Wood is a wonderful natural product and fits beautifully in the garden. If you are handy, you can even build your dream barrel yourself.
Wooden barrels are held together by so-called tension hoops and are therefore very robust. In any case, make sure that your rainwater tank never dries out completely, otherwise the wood will warp.
If impregnated, the rain barrel will also survive the winter. The best thing to do is to empty it completely and place it upside down on the lid. If water remains in it, the barrel may be blown apart by the force of the ice.
What are the characteristics of a metal rain barrel and what are its advantages and disadvantages?
To prevent the metal container from rusting, a high-quality metal rain barrel is usually hot-dip galvanised, painted, powder-coated and lined with plastic. This provides excellent corrosion protection for many years of rain.
A large metal water tank is more likely to be bought anyway if there is a really large demand for water on a permanent basis. But please don't buy a metal barrel in which oil was previously stored. Oil drums are very difficult to clean. And oil in the collection water is not a good idea.
What are the characteristics of a stone rain barrel and what are its advantages and disadvantages?
Unfortunately, you will hardly find a rain barrel made of real stone, because it is all about design in this context. The colour sandstone often looks very pretty, or a rainwater storage tank with a brick or rocky look very natural.
Stones therefore only serve as supplementary decoration. It is usually a combination of a lattice frame (gabion) that can be filled with stones and a pond liner with fleece in between.
What distinguishes an amphora-style rain barrel and what are its advantages and disadvantages?
If you like Mediterranean flair, an amphora is a good choice. This way, your eyes can enjoy the sight of the pretty terracotta look.
However, such a rain barrel is usually made of plastic. Polyethylene has one advantage: it makes the amphora UV-stable and weatherproof. In southern countries, amphorae are traditionally made of clay.
Buying criteria: You can use these factors to compare and evaluate rain barrels
In the following text, we inform you about the most important criteria and categories you should look for when buying a rain barrel.
These are the points in question:
- Child safety lock
- Cleaning effort
The capacity that suits your needs is determined by the combination of precipitation supply, demand and storage space. As we know, we have no influence on the weather. So how do you find the best possible option for you?
Did you know that a household of four can save up to 70,000 litres of service water through rainwater harvesting?
If you use rainwater as an alternative to industrial water, e.g. for watering, flushing toilets or washing machines, you can save quite a bit of water. The actual amount depends, of course, on the condition of the roof and the local rainfall.
If you don't have a green thumb or only have a little time for "balconies", then you will get by with a small barrel. If it regularly overflows, you know: It's time for a connection set and bin number two.
If your heart beats with passion for your garden and you perhaps enjoy the luxury of a large garden or a greenhouse, then it is better to take a large bin or connect several bins together.
You can use several individual bins distributed around the garden as water stations, for example. This shortens the distance you have to walk back and forth with the watering can.
You have chosen the right capacity when
- your bin does not overflow all the time,
- the water is always replaced due to regular use and therefore does not tip over,
- you can always supply your plants with sufficient rainwater,
- you only have to use tap water very rarely, and
- you do not have the feeling that you have lost valuable space since you became the owner of a rainwater storage tank.
A bulbous, round barrel shape makes sense wherever you have room for a good stand and/or a stable base. The larger the barrel, the heavier it becomes as the water level rises.
It can happen that the ground underneath it gives way and the barrel sinks unsightly into the ground or even tips over. Repositioning a full rain barrel afterwards can be quite a feat.
To give you an idea, we have compiled the average dimensions of a round 500-litre rain barrel in the example:
|approx. 1 m||approx. 80 cm|
If you don't have room for pot-bellied, round rain barrels, you can opt for narrow or square rainwater storage tanks. While narrow is usually synonymous with particularly high, angular containers are usually compensatingly longer in shape.
So that you can compare the dimensions with a round rain barrel, you will find the dimensions for a square 500 litre rain barrel in the table as an example:
|approx. 124 cm||approx. 80 cm||approx. 93 cm|
They score with a lot of volume without demanding much space in terms of height. This type of wall tank also fits very well visually against any house wall. Less height often means better stability because the centre of gravity is more favourable. The height is also an important criterion if the bin is filled via a downpipe.
In order not to be restricted in its use, it should be able to fit well under the downpipe. Caution: If you want to be able to place the watering can in front of it, you may need to add a base underneath, which increases the overall height even more.
If the space for the rain barrel is limited vertically or horizontally, you should measure the possible space before buying. Otherwise, it is advisable to think about a security system for taller barrels. Who wants to be around when a filled rain barrel starts to sway?!
The ideal weight of a rain barrel makes it easy to handle when empty. Maybe you want to change the location? Or you need to be able to place the barrel upside down for winter storage so that no damage is caused by ice.
In the best case, both should be possible without much effort when the rain barrel is not filled. Nevertheless, it should be robust enough to withstand the pressure or weight of the water.
For each litre of water, you can estimate a filling weight of about 1 kilogram. With 300 litres, that's a big load. However, if the rain barrel is too light, it can quickly be blown over by the wind.
Plastic is sometimes better than its reputation. The classic green plastic rain barrel can serve for several years before it becomes brittle or leaks and has to be thrown out with the bulky waste. The welded seams are susceptible to repairs. Of course, being made from one piece has its advantages.
Wood, on the other hand, requires a lot of care so that it does not warp, for example. Regular sealing is obligatory here. In many cases, the inside of wooden barrels is therefore lined with a foil. This reduces the wood's constant contact with the collected rainwater.
Ultimately, however, it does not protect the barrel from heat, cold and what the rain barrel is intended for: contact with the water from above. In any case, oak wood or larch wood are very grateful and good-natured materials.
As is so often the case, the same applies here: Quality has its price. Robustness and a decent wall thickness make the rain barrel stable. High-quality material makes it weatherproof.
Colour and look
Although classic colours such as green, blue or grey blend in well with the house and garden, if you do a little research on the internet you will notice that these are not necessarily the most popular colours.
The function of your rain barrel is not affected by the choice of colour. However, the darker the colour, the less UV-sensitive it is.
However, the number of suppliers of colourful and brightly coloured barrels is manageable. That's why you can find lots of ideas on Pinterest, among other places, with which you can embellish your rain barrel afterwards.
For the time being, you can go for the classic and later, depending on the surface, apply paint, airbrush or attach wood or bamboo mats to it.
Bear in mind, however, that due to the weather, you may well have to renew a look you have created yourself from time to time.
Ideally, you should choose a manufacturer who also sells accessories. This increases the chance that you will be able to buy everything that fits. If this is not the case, it helps if the desired connections are at least already prepared.
Of course, a cover only makes sense if it really fits. Therefore, if you buy a lid that is not made for your model, please take a close look at the backfacing. If a lid has hinges or handles, these can be weak points for algae formation.
Since an outlet tap is in frequent use, you should make sure that it is of good quality. If the inner diameter allows sufficient water flow, nothing stands in the way of pleasant use.
Buying cheaply will quickly cost you money later on for repair attempts. Metal taps are definitely more popular than plastic ones. If the connector fits well, everything is tight. A metal thread can also withstand a lot.
For a base to be able to support safely, it should have a decent wall thickness. Thin-walled bases with a thickness of a few millimetres can quickly collapse under the load of a full barrel. If a base seems too soft, invest a few euros more.
Anyone who has children around them knows that playing with water is very tempting for many children.
In this case, we recommend a rain barrel with a lid that is already included in the delivery. If the rain barrel is not connected to a downpipe and is left uncovered outdoors to collect water, there are some dangers involved.
Unfortunately, the average rain barrel with a capacity of 300 litres or more is already large enough for a child to drown in.
A loosely placed lid only protects at first glance, because it is quickly blown away in a light wind. If a child tries to climb into the rain barrel, the lid - if there is one at all - will quickly tip to the side if it is loaded from one side.
To make the lid childproof, you can ask at the DIY store for a childproof lock with a bayonet catch or buy special screws to fix it in place. These also serve as a good wind protection.
If you do not want to close your rain barrel completely, you can place a metal grid on top and connect it firmly to the edge of the barrel.
The more sunlight that falls on the collected rainwater, the higher the probability that algae will quickly grow. Some algae unfortunately favour the accumulation of pollutants in the plant. If you don't want to get to know them and clean them away, use a lid.
For the sake of the environment, it is worthwhile to clean only with water and a brush. For stubborn dirt, you can use vinegar. Chemical cleaning agents should only be used in cases of absolute hardship and should be rinsed out well.
Be careful with wall tanks, which are often a completely closed system. Here, the cleaning attempt can degenerate into a project with a high-pressure cleaner. If it really has to be a closed system, then it is essential to fill it only via an intact filter from the very beginning.
Facts worth knowing about rain barrels
Finally, in the last section we would like to tell you a few interesting things about the rain barrel. Here we deal with the choice of design but also the repair.
Which design should I choose?
Whatever you like is allowed. This also applies to rain barrel design. As we all know, variety makes life colourful. Whether round, square, large, small, flat, narrow or folding - the different looks range from rustic wood look to Mediterranean design to noble granite look or sandstone.
If you can't find what you're looking for, you can of course paint your rainwater tank or decorate it with graffiti. If you're brave, you can also go for bright colours instead of the typical green, blue or anthracite.
To prevent the paint from peeling off, it is best to prepare the surface. Depending on the material, you can do this with sandpaper, for example. This makes the paint last better and you will be able to enjoy your work of art for longer.
Make sure that the paint does not penetrate the inside so that the quality of your water is not affected. If you're not much into painting, you can integrate a plant bowl for decoration and fill it with colourful flowers.
What accessories are available for rain barrels?
A rain barrel is a practical thing in itself, but with the right accessories it can be used much more comfortably and sensibly. We have listed below some extras you should think about when buying a rain barrel.
Lid & filter
To ensure that only water ends up in the rain barrel and not dirt, you need a suitable lid and a filter. The filter in the downpipe to the barrel prevents leaves and flowers from falling into your collected rainwater. These can make your rainwater rotten when they decompose.
The lid prevents insects from colonising your water or small animals from falling in and drowning in your water tank. If you have children, a lid with a child safety lock is recommended.
The lid and filter thus protect against contamination in general and thus against germ formation. Both are often included in the purchase price.
A pump is not absolutely necessary. It does, however, make you more flexible when it comes to the location of your rain barrel. It is more suitable for large-scale watering. You can connect lawn sprinklers and garden hoses. Depending on the use, however, the pump must be able to generate the corresponding pressure.
If you want to be independent of a power supply, choose a swing pump. This is a hand pump with which you can quickly fill water with a little arm muscle strength.
Lid, filter and pump are just the beginning. The range of accessories you can add to your rain barrel(s) is huge. If you want to delve further into this topic and perhaps even become a rain barrel professional, then also take a look at the following accessories:
- Level indicator with sensor technology or ultrasound measurement
- Drip irrigation
- Connection set
What do I do about animals in my water barrel?
Unwelcome guests such as mosquitoes, tadpoles or water fleas can be prevented in part with a net or, in any case, best with a lid.
You can recognise water fleas as small, white spots in the water. They are not a threat to humans or plants. Like frogspawn, they are often brought into the water by birds that come to drink from your rain barrel without a lid.
If you discover gnats, the situation looks more serious. They can quickly become a nuisance. A few drops of vegetable oil in the collection water can help.
Oil is a natural home remedy against gnats and an environmentally friendly solution that makes the water still usable for your plants. If you have missed the right time to intervene, the only solution is to empty the bin completely.
For many animals, rainwater is a fine thing. But beware: rainwater may be too acidic for the fish in your aquarium! Inform yourself thoroughly before using it. Your fish will thank you.
How can I repair my rain barrel?
Unfortunately, repairing a rain barrel is not always easy or cheap. But it's definitely worth a try before a good-as-new barrel with a crack ends up in the rubbish.
Before you throw your rain barrel in the rubbish, you can try to repair it.
If you are lucky, a soldering iron or a hot glue gun will be enough if you have the right knowledge of materials. Most of the time, however, the materials are either difficult to glue or you need to know how to weld plastic in order to make your rainwater catchment tank leak-proof again in the long term.
It is best if you can also fuse equivalent plastic. This makes the fracture stable and resilient again. Caution is advised in any case, because plastic and high heat are only compatible to a limited extent.
For a nicer look, you can then remove any unevenness on the dried area with a file or sandpaper.
In order to avoid the need for repairs at an early stage, you should not only take good care of your rain barrel, but also pay attention to the duration of the manufacturer's warranty. The longer the warranty, the higher the quality of the material and workmanship.
Image source: pixabay.com / diego_torres