ᐅ Installing a dimpled membrane, moisture protection; basement insulation, adhesives

Hello,

I would like to install the dimpled membrane (dimpled membrane + fleece + foil) myself. However, I still have a few questions.

1. How do I attach the dimpled membrane to my basement wall (precast basement + perimeter insulation)?
I have received conflicting information. Some say the membrane must be fixed with bituminous adhesive, while others say it is sufficient to secure it with nails and vertical wooden battens.

2. The dimpled membrane I can get has a width of 2 meters (6.6 feet), and our basement walls are about 2.75 meters (9 feet) high. How should the membrane be installed in this case? Here, too, I have heard different advice from building center experts.
Some told me that the membrane must be installed like individual wallpaper strips—vertically. Others say it should be applied horizontally over the insulation. Since the basement height is about 2.75 meters (9 feet) and the membrane is only 2 meters (6.6 feet) wide, an additional strip must be placed above. Should the dimpled membrane be installed with an overlap in this case?

Thank you very much.

I'll join in here. During the installation of a drainage system (previous owner), the dimpled membrane was very unattractively extended all the way up to the brickwork.
Research has revealed completely opposing opinions on the subject of dimpled membranes. For example, whether the dimples should face inward or outward.

The real question is why you want to install a dimpled membrane on top of the perimeter insulation. What material do you have available for backfilling?

Hello,

thank you for the quick response. We are getting a prefabricated basement. The manufacturer explained to us that we should install a dimpled membrane as protection for the perimeter insulation during backfilling. I know that in this case, just a plain dimpled membrane is sufficient (the fleece and the foil are actually not necessary). However, the price difference is quite minimal. We will use recycled material for the backfill. If I don’t install the dimpled membrane despite the construction company's recommendation, there will probably be major disputes regarding warranty claims. The foil is not that expensive, so I don’t want to take that risk. My question now is not whether to use it or not, but how to do it properly.

Best regards

Hello,

the basement will be completed using precast waterproof concrete. As far as I know, only the joints and corners are coated with a thick membrane. After that, the perimeter insulation will be installed, which will likely be glued or fastened with anchors. Finally, a drainage membrane (dimpled membrane) will be attached to the basement wall for the area in contact with the ground.

Regards

Answers and more questions...
1.) Basement with waterproof concrete (WU): The real question is what the actual load case is. Or why waterproof concrete?
2.) Waterproof concrete basement without waterproofing but with perimeter insulation: What is the intended use of the basement? Insulation implies it will be "heated," heating indicates higher quality use, but the missing vapor barrier of the waterproof concrete does not align with that.
3.) Perimeter insulation: What material was used, and is moisture protection even necessary?
-> This again raises the question of the load case...

Do you want to just ignore all of this because

...there will definitely be a lot of fuss with warranty issues...

you should ask yourself on what basis the services are currently being provided and how this will be handled in the event of a warranty claim. In the worst case, the company will tell you that you a) did not provide a waterproofing plan or b) did not supply a soil report, so they didn’t create one either and therefore everything was installed according to standard procedures and a typical, off-the-shelf approach. And somewhere along the line, you probably already approved all of this with your signature.

What exactly do you hope to achieve by intervening yourself in the waterproofing of your basement? The two hours of work you save from someone who knows what they’re doing won’t be worth it.
That also raises the question of the contract scope. There may be trouble later *because* you interfered with the construction process. If the basement builder wants that, he should provide you with a written explanation of why it is necessary and why it is not included in his scope of work.

At the moment, in my opinion, the only argument in favor of the three-layer membrane is that the backfill material seems very coarse, which could cause minimal damage to the perimeter insulation.
By the way... incorrect installation of your dimpled membrane could already cause significant damage here.
And... one more thing... forget the pictures on the websites of a well-known large manufacturer, forget the neighboring foundations, and forget the things your basement builder says.
The dimpled membrane is a dreadful topic that is probably installed incorrectly in at least 50% of all cases.

I would be curious about the basement builder’s written justification (referencing applicable standards).
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