ᐅ How large is your rainwater cistern?

Hello,

We have a 450 sqm (4,844 sq ft) plot and want to install a cistern. Is 7 cubic meters enough, or is it better to plan for 10 cubic meters?

How large are your cisterns?

Best regards,
housedreamer

Maybe I’ll expose myself again as an uninformed layperson, but isn’t it about the sealed surface area or the roof area that needs to be drained?

Oh, it’s simply about how much water comes in (rainfall on the area to be drained) and how much water goes out (garden irrigation / domestic water system / snow cannon, etc.). One shouldn’t forget that the overflow of the cistern should occasionally activate; otherwise, too much debris accumulates inside the cistern.

We have 4.5 cubic meters (160 cubic feet) – that’s enough for our garden irrigation only. But of course, it depends on how much you need to water and how intensively you do it...

Do you want to or do you have to? If you don’t have to, then calculate carefully—it usually isn’t worth it.

We have slightly over 10 sqm (107 sq ft) total volume and 5 sqm (54 sq ft) retention volume.
That was the regulation in our area.

I have already heard everything about this, from "way too large" to "it can never be too big," although I wouldn’t support the latter because of the previously mentioned overflow.

It depends on the factors mentioned in earlier posts (sealed surfaces, usage behavior, etc.).

Hello, what does the development plan say?
For us, 5 cubic meters was mandatory, but we built 6.5. The cost for the additional 1.5 cubic meters was minimal.

What do you want to use the cistern for?