Base slab - What to pay attention to before pouring?

Hello everyone,

With us, things are slowly but surely moving towards the end of the demolition/excavation and the preparation of the base slab. A few days ago, I read a topic here about incorrectly laid pipelines and would like to prevent such problems embedded in concrete.

The question is whether there are general tips on what to pay attention to before pouring the base slab. Logically, this primarily concerns everything that is laid under or in the base slab. So far, my list includes:

[*]Correct distances / dimensions of wastewater pipes
[*]Proper execution of ring earth electrode, connection tabs for equipotential bonding and external lightning protection

The ring earth electrode, of course, must be checked before the base slab, as it lies under the clean layer. That’s my own list, which is obviously rather short. Are there any other aspects?

Does it make sense to tell the shell builder that, before the concrete is poured, you want to have an "inspection appointment" with the architect, lightning protection company, and sanitary company to prevent any problems?

Many thanks in advance and best regards!

The reinforcement in the concrete slab itself must be connected to the foundation earth electrode at intervals of 2m (function potential equalization). Only to be carried out by the electrician or directly under his supervision. The foundation earth electrode as well. Everything must be documented, in pictures and forms. Important!!!!!

We had a report from the electrician about the foundation earth electrode. He took some measurements there.

The installation of the drain pipes was done by the plumbing company.
What do I want to check there? I don’t inspect every step the craftsmen take. I would initially trust them to do it properly. It might make sense to check the position of the pipes after the floor slab has been poured. If there is time, even before that. But usually, everything happens very quickly one after another.
I wouldn’t have had the opportunity to check it in between.

It would be annoying if a mistake was made there, but how often does that happen?

If you follow this approach further, you would also have to continuously check all measurements of walls and installation lines during construction.

Have an independent expert inspect the house at certain construction stages and that’s that.

And whenever you are on the construction site, walk through the house with a watchful eye and, if necessary, a tape measure, and calmly take a good look at everything.

Thank you both for the feedback, it has already helped me!

What do I want to check there? I don’t check every step the craftsmen take?

Certainly not every step, but from my point of view, there are milestones before which it’s worth taking a closer look. From my perspective, that is definitely before creating concrete facts with the foundation slab.

If you take this approach further, you would have to continuously check all dimensions of walls and installation lines during construction.

I consider it a given that I regularly check during the construction period in collaboration with the architect whether everything fits. The interval and level of detail of the inspections are for me derived from the perceived working method of the respective trade.

For installations in KS or drywall, I overall see it as less critical than for things embedded in concrete.

Have an independent expert inspect the house at certain construction stages and that’s that.

Currently not planned, but I will think about it again!

And every time you are on the construction site, walk through the house with a watchful eye and a tape measure if necessary and calmly look at everything.

That was planned anyway – and especially for that I was hoping for tips regarding "typical" weak points.

There are two possibilities. You have a good shell builder and you have to check little, it runs smoothly. You have a bad shell builder and all your control will not help you.

There are two possibilities. You have a good structural builder and have to check very little, it runs smoothly. You have a bad structural builder and all your checks won’t help you.

According to the feedback so far from acquaintances and friendly craftsmen: the first. Of course, there is no guarantee that it will be the same during construction – but I think we will do quite well with the structural builder. Things tend to get forgotten anyway, whether intentionally or not. I don’t want to assume bad intentions. But hey, just for the good personal feeling and conscience, I like to simply check over things myself. I can always be annoyed afterwards – but then at least I can’t blame myself for not visiting the construction site more often.