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Choosing the right size rainwater tank for your home

Rainwater Tank

Water supply is crucial for the daily running of the home. This is because many activities at home such as cooking, cleaning, washing clothes, bathing, and many more rely on the availability of water. For this reason, water shortage can be a frustrating occurrence for everyone involved. Therefore, as a homeowner, you may want to expand your sources as much as is possible. Trapping of rain water is a great way in which you can achieve this. Still, a lot of planning is required to make this possible. In addition to constructing a water collection system, you also need a tank to store the water that is collected. The following are some of the things you should consider when choosing the right size rainwater tank for your home. 

Amount of Water Needed

Rainwater can be put to use in many various ways around the house. You may start your research by determining the amount of rainwater that would be enough to satisfy all these uses. The first step is to determine the specific areas that you want rainwater to be used in. You then need to find out how much water is required to carry out a single cycle of a specific activity, and how many cycles are carried out weekly. With this, you can now calculate the amount of water that particular activity will use on a weekly basis. Do this for the rest of the uses and add all of them to get the total weekly amount of rainwater that you would require.

Rainwater Tank Collection Capacity

Your water harvesting capabilities will depend on the amount of rain at that given time as well as the size of your roof. The bigger the roof, the more you are able to collect. You can determine your potential in terms of water collection by applying the rule that states that 1 mm of rain on a 1 cm2 roof will cumulate 1 liter of water. If you have a 100 m2 roof, a 20 mm rainfall will give you 2000 liters of rainwater. Although, this is based on the assumption that all the down-pipes drain into the tank. Otherwise, you will calculate depending on the percentage of those that do so. Depending on the average annual rainfall in your region, the size of your rainwater tank should allow you to collect the highest amount of water possible that will last you between rain episodes.

Space Availability

With both the amount needed and the amount that you are able to collect in mind, you are now likely to have an idea of the ideal rainwater tank capacity that you require. Nonetheless, you still need to consider the space available for the tank to fit in. By translating the tank capacity from liters to volume, you will be able to come up with dimensions that will lead to the best utilization of the available space. This can be based on the fact that 1000 litres amount to 10 m2. The smaller the area of the space allocated to the tank, the longer the tank should be.

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All things considered, the size of your tank will still depend on what you can afford. The higher the capacity, the more expensive it will be. If you are working with a strict budget and you feel you have to get a big tank, you might have to compromise on the design and maybe even quality, for the size you need. Otherwise, you have the liberty to choose the size and design that works for you. At the end of the day, you need something that fulfills the intended purpose while sticking to the budget. 


How easy is it to access the intended location of the rainwater tank? The answer to this question will determine the shape as well as the material of the tank. This is because the tank should reach its destination without any damage.


This predominantly depends on whether you care for the attractiveness of the tank or just want it to be functional. If it is going to be placed in a conspicuous place, then you may look for a more appealing design such as a corrugated stainless steel tank or a colorbond slimline water tank. If not, then a simple normal one will do, such as a rubber one.

Slimline, Steel, Colorbond. There are plenty of options when it comes to rainwater tanks. Contact Redshaw Plumbing & Drainage today to discuss your Rainwater Tank needs today.

For more expert advice on the best rainwater tank for you contact Redshaw Plumbing & Drainage today.  With locations in Ipswich, Toowoomba, Brisbane and Gatton, we have a wide range of rainwater tank brands from bushmans water tanks to sturdy aqualine steel tanks. We have the right rainwater tank for your needs and budget.


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