ᐅ DIY – Concrete-Effect Bathroom Vanity

Perhaps some of you have already tried something similar.
I am looking for a washbasin for the main bathroom with a concrete-look finish, as real concrete would be too heavy.
After a long search online, I came across various suppliers.
Basically, it would come down to a coating with so-called microcement, which is then sealed to be waterproof.
What I have not yet figured out is how to construct the washbasin itself.
I’m not quite convinced that MDF, for example, would be a good choice.

Attached is a picture to roughly illustrate what I have in mind:

I would now recommend the green drywall boards. These are also used for pre-wall installations and raised platform encasements, which are then properly tiled.

It could be an option.
However, I would need to test whether the coating is hard enough for a sink.

There are so-called building boards available in different thicknesses. These are suitable for this purpose.

Sven Backstein is a specialist—especially when it comes to these kinds of plans. He knows his stuff, runs a shipping service for all kinds of concrete materials, has a forum on the subject—and is really generous with his advice. I have learned from him:

Concrete is what you make of it!
And you can do much more with concrete than I previously thought.

When it comes to "making concrete lightweight," "foam concrete" comes to mind. A brilliant invention...

What have you decided on now?

I think the green drywall boards are suitable. Microcement can also be applied on OSB boards. Since microcement seals the underlying material waterproof, the substrate should hardly matter?