Apartment blocks must have a childrens playground

We own a Eigentumes Wohnen in Bremen. All the owners are retired/older. One sperate Building has 5 Apts. and most one bedroom. The second Building in the Separate weg has 6 Apts. The Management bills us seperately because they are separate buildings facing different streets. We have a very small common area.
The renter in one building wants to take the very small area and put in a large sandbox for his grandchild who does not live here.
My Management says this is a rule in Germany that all homes must have a play area. I can not believe that if all are old people that you must allow a sand box when none of the owners want a box.
Does anyone know where to look for the rule on this situation?

The Mieterverein. Not here.

I think it is all complexes over a certain size or with more than a certain number of home units. So, check with a lawyer or the mieterverein, there is something to it.

yep - they have to have one, however, when the guys from the city come to check building is ok, then you can pull it out -

we have a sand pit that I'm sure noone will use - Once the council guys have checked the renovation then the owners will agree to get rid of it!

in your case you may have to vote to get rid - BUT maybe in this case you have to keep it, even if only one person says so :-(