Determine if wall is aerated concrete or 'real' concrete?

[LarsOo]

Hope this ends up in the right forum section.

How can I, as an enthusiastic amateur, distinguish if a wall is made of lightweight concrete or real concrete without damaging the wall? I have noticed a significant difference when drilling in lightweight concrete and concrete, but I'm unsure if I can hear the difference just by knocking.

At the same time, it would be interesting to know if a wall made of lightweight concrete can be load-bearing or if it must then be real concrete.

Grateful for answers.

 

[SBH]

Concrete sounds harder than lightweight concrete.
Yes, it can be load-bearing.

 

[nimhed]

It cannot be ruled out just because it is lightweight concrete.

SBH got there first.

 

[anaitis]

An almost completely non-destructive method is to unscrew a wall switch or a wall socket.
Then you can feel with a small screwdriver on the side of the box.
If you can push the screwdriver in, it is lättbetong.

 

[Taken]

Just tap a little on the wall, you clearly hear/feel the difference. Extra easy if you have walls of both types near each other so you can compare.

 

[LarsOo]

Thank you for the answers. I didn't notice any significant difference between the inner wall in question and an outer wall. I assume that outer walls are rarely made of lättbetong and can therefore act as a 'guide'?

I will try at the electrical outlet, that sounded like a safe trick.

 

[anaitis]

I assume that external walls are rarely made of lightweight concrete and therefore can act as 'proof'?

Not at all unusual with external walls made of lightweight concrete.

 

[snuttjulle]

Not at all particularly unusual with outer walls in lightweight concrete.

I agree. In a building I lived in for a few years (apartment building) all the interior walls were made of very hard vibrated concrete with a lot of reinforcement, but the outer walls could scarcely hold up the curtain rod.

 

[LarsOo]

Next question. How can I find out if the wall is load-bearing or not? The building was constructed in 2000, so plans should be well preserved.

 

[Mikael_L]

It is very common, almost to the point where you think it's the most common, to have outer walls in apartment buildings made of lightweight concrete or some kind of framed construction with drywall facing the living area.

It's probably some kind of smart way to build the load-bearing structure while also getting better sound insulation and good fire protection between apartments.

If you live in a condominium, the association should have access to the plans.

 

[LarsOo]

How can you tell from the drawing if it is a load-bearing wall? Markings/codes/other?

 

[Mikael_L]

I actually don't know, but maybe someone else does ...