Running a washing machine from a rainwater harvesting tank

Would appreciate any help on this. We were thinking of moving our washing machine and dryer into an outdoor shed and were wondering is it possible to work the washing machine off a rainwater tank specifically attached only to it?

Would there be an issue with the pressure/quality of water/amount needed etc? Any advice appreciated. Didn't want to waste a plumbers time bringing him out to quote if it was a non-runner.

Just make sure you don't put on a whites wash when those Sahara sands come down in the rain. Then there's the insects etc that are going to fall into the tank and then into the washing machine.

I wouldn't use rain water to clean my clothes. Too big a chance of ruining clothes by using dirty water.

yeah i was worried that might be an issue, would a filter solve that issue? Other sites recommend rainwater as it's softer!

paddi22 said:

Would appreciate any help on this. We were thinking of moving our washing machine and dryer into an outdoor shed and were wondering is it possible to work the washing machine off a rainwater tank specifically attached only to it?

Would there be an issue with the pressure/quality of water/amount needed etc? Any advice appreciated. Didn't want to waste a plumbers time bringing him out to quote if it was a non-runner.

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You would need to make usure that you have enough pressure and also gravity from the rainwater tank for this to work.

Also you need to filter the water to a stage that its clean enough to go through a washing machine and not block it up.

You would need 3 stage filtration to make it clean enough for washing clothes.

If you want to use it for showering,then you need UV sterilising system.

We are currently installing a 9000 litre underground system with full filtration and UV system.

It's possible alright, but there are a few things you'll have to be aware of and plan for.

It varies across the country, but in Dublin for example, you'll collect 760l per annum on average from 1 square meter of horizontal roof area. During the summer months, rainfall drops to as little as 30l over the course of a month. A washing machine will use 50-60l per wash, look up your manual to determine what yours uses.

So, worst case, each 2 sqm of roof area will collect approx enough water on a monthly basis to run the machine once. How often do you run the machine typically?

The water will also need to be stored at a height to create a hydrostatic head and deliver at sufficient pressure as required by your machine. Again, the manual will likely give an indication of the minimum pressure required. Storing at height around a shed may cause issues, remember 1000l litres of water weighs a tonne. You may also need to introduce a pump to get the water to raised storage.

You will also need filtration to remove the general debris (plant, insect, bird droppings, etc.) from the collected water. But filters to clean the water to the standards required for washing aren't too expensive.

Leo said:

It's possible alright, but there are a few things you'll have to be aware of and plan for.

It varies across the country, but in Dublin for example, you'll collect 760l per annum on average from 1 square meter of horizontal roof area. During the summer months, rainfall drops to as little as 30l over the course of a month. A washing machine will use 50-60l per wash, look up your manual to determine what yours uses.

So, worst case, each 2 sqm of roof area will collect approx enough water on a monthly basis to run the machine once. How often do you run the machine typically?

The water will also need to be stored at a height to create a hydrostatic head and deliver at sufficient pressure as required by your machine. Again, the manual will likely give an indication of the minimum pressure required. Storing at height around a shed may cause issues, remember 1000l litres of water weighs a tonne. You may also need to introduce a pump to get the water to raised storage.

You will also need filtration to remove the general debris (plant, insect, bird droppings, etc.) from the collected water. But filters to clean the water to the standards required for washing aren't too expensive.

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Cheap as chips from ebay suppliers when compared to irish suppliers.

great advice as always, much appreciated. I'l root out the manual and see what kind of figures I would be dealing with.

Never mind the rainwater harvesting , putting a washing machine in a shed didn't work for us.

The Weather?

what issues did you find with it in the shed?