Base sealing according to technical drawing

Hello everyone,

in another . To assess the damage, a building expert from a large nationwide company specializing in building waterproofing stated that my base is not properly sealed.

After reviewing the documents with my prefabricated house builders, I have a different opinion except for the entrance area.

How do you assess this? Did we do something wrong with the building base, and is a continuous base waterproofing with multilayer sealing compound application from 30cm below ground level really necessary? If that is the case, I would have to redo the entire exterior plaster on a prefabricated house – that somehow does not seem constructive to me and certainly was not what the "homebuilder" intended (since they were also responsible for applying the exterior plaster). The base is plastered with a base coat.

I have attached the technical drawing of the base and a few impressions of my splash protection.

Thank you very much for your assessment
Andreas

Good evening,

first of all the question: Which documents have you studied? At first glance, one can initially agree with the expert here.

The base waterproofing must be carried up +30cm above the finished surface (outside) on the construction. So behind the plaster. With which product and which type of waterproofing depends mainly on the exposure to water.

When I see the drawing, no base waterproofing has been carried out here, so this is technically incorrectly executed. I do not quite understand your comment about 30cm below ground level here, or do you mean above ground level, as I described above?

You of course have to carry the waterproofing into the soil and depending on the water load also "anchor" it, but I am currently not aware of the 30 cm.

Regarding the base plaster: It also apparently was not drawn, but is required according to DIN. This must be carried 5cm above the finished surface. You apparently have carried this out. However, it is important here that it is not just a dark-colored plaster, but a moisture barrier from the system manufacturer (for example, Sto calls it Flexyl, Brillux says it can be omitted in their system if the correct reinforcement is used, etc. – so check the manufacturer's portfolio here).

Best regards, Jann

Good evening,

first of all the question: Which documents have you studied?
At first glance, one can initially agree with the expert here.

The base waterproofing must be carried up +30cm above the surface covering (outside) on the construction. So behind the plaster.
Which product and which waterproofing method depends mainly on the water exposure.

Since we bought the house turnkey including plaster, I assume that the builder waterproofed the building structure according to DIN18195. We did not receive any special instructions for the base. You can also see in the area of the openings (doors) that there is a black waterproofing behind the plaster. However, I will have this confirmed again. The floor slab is made of waterproof concrete, the floor slab is waterproofed from above with bitumen sheets.

When I look at the drawing, no base waterproofing was executed here at all, so this is professionally incorrect.
I don't quite understand your comment about 30cm below ground level here, or do you mean above ground level, as I described above?

Exactly - that is what I mean.

Of course, you have to lead the waterproofing into the soil and also "anchor" it depending on the water load, but I am currently not sure about the 30 cm.

Regarding the base plaster:
This apparently was not drawn either, but is required according to DIN. It should be led 5 cm above surface covering. You apparently have carried this out. However, it is important here that it is not just a dark-colored plaster, but a moisture barrier from the system manufacturer (for example, Sto calls this Flexyl, Brillux says that in their system it can be omitted if the correct reinforcement is used, etc. – so check the manufacturer's portfolio here).

Ok. This is certainly not properly executed. In your opinion, what needs to be done now? At the moment, I would exclude that something has to be done to the exterior plaster.

My question is what I should have done to ensure that the damage at the base is correctly plastered or waterproofed. What would you do now and especially how?

Is it sufficient to waterproof and re-plaster the base, or is the problem actually with the building structure? Who is liable for this damage and is it something to be considered by the builder (general contractor) or the landscape gardener? Who is responsible here?
Thank you for your help

I don't quite understand it yet. Have you now created a base sealing or not? So outside the entrance area?

What exactly is your structure? You have a timber construction, right?

How do you now know from my statement that the splash protection at the base area is not correct?

Could you perhaps fundamentally explain the problems and findings once again and explain the entire structure of the base?

These would be exemplary connections for plaster / ETICS

Hello,

no - after consulting with our home builder at the time, no separate base waterproofing was necessary (in case we keep 15cm away from the base). Therefore, we did not waterproof the base at that time, but only plastered and painted over the insulation. Unfortunately, I can no longer trace which base plaster that was or is.

Since we are now (due to the damage to the exterior plaster - see another post) on the lookout for what might have gone wrong and where we might have problems (could be), we have become aware of the base and the base waterproofing.

So - regardless of the reveal area in the doors, my assessment is - the base waterproofing is completely missing.

We have the base made of WU concrete + 80mm Styrodur insulation, then 2 layers of base plaster + paint. The house is a timber frame with WDVS. Apart from the vertical base waterproofing (from the drawing), everything else has been done.

Hi,

Ok, you have no base waterproofing - understood.

in case we stay 15cm away from the base).

I don’t understand that. Do you mean the gravel strip? Because you stay away from it with the covering or do you mean that your base plaster (outlined in black) is 15cm lower? Or the 15cm related to what?

When I look at the picture of the plaster you sent, I don’t see why it would be OK to waive waterproofing.

In my opinion, your "home builder" told you nonsense.

As I understand it, we can explain it in more detail via video or however you want, the "home builder", meaning the construction company, is to blame. Waterproofing must not be waived. Your damage with detachments in the plaster can also result from the construction drawing in water and then releasing it again through the plaster; so it does not have to be absorbed only via the plaster. If this were the case, a moisture barrier would help, but I wouldn’t promise that.

Especially since you are working with wood, I would be particularly careful regarding moisture.

How many years ago did you build? Is it more than 5 years ago?
If it’s less than 5 years ago, you still have warranty liability from the builder that, in my opinion, covers the damage.
If it’s longer ago, since a technically necessary service was not provided, you might still be able to claim damages with the help of a lawyer.