Base plate - Reinforcement / Sink & Quality

Hello everyone,

our house construction has started and the first steps such as earthworks and strip foundations have already been completed. The base slab has been prepared for concreting.

I have the following questions:

Earthworks:
For the earthworks, according to the soil investigation, 60 cm of topsoil was removed and replaced and compacted with fill sand accordingly. However, it has been shown that on one side of the house in the area of the strip foundation, about 10 cm were removed too little (see photo in the attachment). How critical do you see something like this?

Strip foundations:
The strip foundations (80 cm deep with round cages) were not shuttered. How can the L-barrier be properly applied later here without a clean edge? What do you think about the inserted irons currently used as holders for the formwork?

Base slab:
Hauff sleeves for wastewater penetrations were installed in the base slab, which I see as positive. However, it is also visually apparent that the sand bed in the middle of the slab has a strong depression. Upon closer inspection, extra thick reinforcement can also be seen there. Could this possibly be due to load-bearing walls?

I look forward to your answers, as the slab is supposed to be concreted on 17.12.2018.

What is your overall visual impression?

Thank you very much

My opinion: this is not how you will get through building the house and it will be extremely exhausting. Don't you have anyone who knows about this and can supervise it?

This response does not help me without fundamental reasons.
I do believe that we are quite capable of getting through the house construction. However, that it will be exhausting is another matter.

What matters to me here is the assessment of the aforementioned topics by third parties.
We know each other, partly due to our professions, but there are areas of expertise, as mentioned above, where I would like to hear another opinion.

When the topic of experts comes up:
We had discussions, but they were anything but convincing. One even went so far as to say that I have to work much more responsibly in my job than he does. Also, those visited (by the way from the Bauherren-Schutzbund, which we are now leaving again) were not able to explain a meaningful staging of the payment plan, nor to address further construction priorities.

Hi,

giving a diagnosis from a distance is always difficult. To me, everything looks normal so far. Since your floor slab is a ground-contacting component, a vapor barrier will be installed inside anyway. The connection to the foundation should not be a problem and the few rebars should also not cause a big issue. The fact that less topsoil was removed than agreed upon should be a matter for the invoice. Topsoil settles significantly less than fill material, even if compacted. The depression is not a big deal; more concrete will just be poured in, at the expense of the contractor. Also interesting is that there apparently is no insulation under the floor slab. This is hardly ever seen nowadays anyway.

As an electrician, I find the topic of grounding/potential equalization more interesting. Normally, the reinforcing steel mats have to be included in the grounding. For this purpose, usually a steel strip is laid all around once and connected to the reinforcing steel mats every 2 meters. This is regulated in DIN18015-1. You should take a look at it before they pour the slab tomorrow.

And installing and documenting this must be done by an electrician, not like before by the bricklayer.

Otherwise, I wish you lots of fun with the house building project!!

Hi,

giving a diagnosis from a distance is always difficult. To me, everything looks normal so far. Since your floor slab is a component in contact with the ground, a vapor barrier is installed inside anyway. The connection to the foundation should not be a problem and the few reinforcing bars should also not cause a big issue. The fact that less topsoil was removed than agreed upon should be a matter for the invoice. Topsoil settles significantly less than fill material, even if compacted. The depression is no drama; just more concrete will be poured in, at the expense of the contractor. It is also interesting that there apparently is no insulation under the floor slab. You hardly see that anymore nowadays.

As an electrician, I find the topic of grounding / equipotential bonding more interesting. Normally, the reinforcing meshes must be included in the grounding. For this purpose, a strip of steel is usually laid all around and connected to the reinforcing meshes every 2 meters. This is regulated in DIN18015-1. You should take a look at that before they pour the slab tomorrow.

And the installation and documentation must be done by a certified electrician, not simply by the mason as before.

Otherwise, I wish you lots of fun with your house building project!!

Hello Tom,

thank you very much for the reply and the wishes.

We decided against the insulation.
The strip steel is installed all around in the strip foundation and is also connected.

Hi, our house was also built on strip foundations and there is nothing negative to say about the fastening with iron. Our construction manager from Prime Massivhaus told us that it is important that the iron is completely encased by the concrete so that it cannot rust. So I wouldn't worry about this issue.