Construction of a 144 sqm bungalow in Fichtenwalde (near Potsdam)

correct. I have "buried" an 8 m³ cistern next to our house. Well, our property is only 700 m² in size. We got through the summer really well. It was only "almost" empty once. One good downpour and it's full again. We have also connected all roof connections, carport, and front paved areas. That adds up quickly. It is about 3 meters away from the house. It was perfectly manageable to install it from the street. I would do it again anytime. :) Since we also built in the water protection area, unfortunately we couldn't do any earth drilling or well drilling either. So unfortunately the only option left was the air heat pump. I might have liked to install trench collectors as well. But my wife did not want that. Also, the property would have been poorly suited for that and she wouldn't have been able to plant her trees anymore.

Is it a concrete cistern? Strangely, those are cheaper than plastic cisterns :-) The garden will be "only" about 750 sqm at the back. The house is quite far into the property. A carport will be built at the front over time, and mostly paved. So that's already 16.5m (distance street -> house) + 13.5m house width = 30m x 20m property width = 600 sqm. Plus a large terrace. That leaves about 750 sqm of garden.

yep, concrete cistern. Ordered from a Berlin online shop. Correct, they were cheaper than the plastic parts. We should still have about 350-400 m² of area left. We also have a large terrace at the house.

Does anyone have experience with ring trench collectors and rainwater cisterns? Especially with the rainwater cistern, I am surprised that it is supposed to be buried so far from the house.

Instead of the cistern, I would put the drainage directly over the ring trench collector. saves money and increases the efficiency of the heating system. works excellently for me

I would place the drainage directly over the ring trench collector instead of the cistern. Saves money and increases the efficiency of the heating system. Works excellently for me

I have now spoken with the external construction supervisor. She confirmed it. However, like probably everything, it must be done correctly. I have now written to the contractor that I want to chat with him about it :cool:

Thank you very much for the quick answers. The 4800€ is kind of a deposit that you get back in the best case?
Since Borkwalde is not our first house, I can share with you our experiences with our two houses regarding your cistern.
We once had a house in Stahnsdorf on about 700 sqm with about 240 sqm roof area; when it got intense during extreme weather, we had Chinese water displays at the downpipes, also coming out of the ground. Then we retrofitted infiltration baskets and had peace. The barrel would have been full quickly. When it is full, where to put the water then, so after that infiltration baskets, which are not cheap either. Not to mention the pine needles; there must be grids in the downpipes, otherwise they all end up in the barrel. The needles get compressed so much that I sometimes had to use pliers to free the pipes again. Of course always in the rain or bad weather. Now we have a rental cabin with 6m3 in the ground. If we connect a suction pump from the landlord there, only a trickle comes out. I would not try to water a large property with that. There are definitely better solutions to have a pump, possibly in the barrel, that produces real pressure. Personally, I wouldn’t know what to do with the 10m3. I am a fan of automatic watering and for that you already need about 2000 liters of delivery capacity to water larger areas properly. I would then have to couple that with fresh water because the barrel is certainly empty in summer at times. For me, that would be too much effort. Also, digging in the rings can of course be done by hand because they settle, but by the 4th ring at the latest the earth must be moved up first, and the cramped feeling in the soil is not everyone’s thing. So technology has to come into play, which of course costs. If after some time something should be wrong with the cistern or you simply no longer use it and want it removed, then in ?? years an excavator will drive through your finished garden. I wonder what my wife would think about that. Then the top ring would have to come off and at least 10m3 of earth would have to be filled back in and the rest of the cistern left in the ground. Knowing my luck, I will want to install something exactly at the spot in the ground where the remaining rings bother me. If I nevertheless decide on water in the garden, I would choose the front garden. We are also planning 15m from the street, there would be enough space. If the cistern is full, you can water longer than three days. You don’t dump 3000 liters into the garden in one evening.

Thank you very much for the quick responses. The €4800 is kind of a deposit that you get back in the best case?

It is a security deposit in case the first trees on the replacement areas do not grow. Theoretically, you get the money back after years, but I don't necessarily count on it :)

I didn't quite understand about the ring trench collectors. They are completely installed by the construction company or the specialist company. So I don't have to worry about it. They are then buried about 1-1.5m deep in the ground. The only disadvantage is that you are not allowed to transplant deep-rooted plants there or build a little house, etc. However, we have enough space behind the house, so we have no problem with that. Also, we have always lived in "small" apartments, so the switch to a house and a big garden is quite an experience :-)

I still have to think about the cistern and talk to the builder. Maybe we will save ourselves the approx. €4,000 investment and find another better solution.