Thinnest and strongest blocks for partition walls?

[MariaD]

As per the title, I’m seeking advice on which blocks would be the strongest and thinnest for a partition wall in order to save money.

I have a few questions that I hope can be answered:

1- I understand that a higher N value means a higher load-bearing capacity. But does a higher N/mm² translate into a more durable block?
2- If a standard block and an AAC block have the same kN value, do they have the same durability and load-bearing capacity when it comes to hanging cabinets?
3- Regarding sound insulation, do AAC blocks have the same insulation properties when compared to standard blocks with similar kN values?

What is the thinnest block I could use for partition walls that has good sound insulation and is strong enough to hang cabinets on it?

I found this one: Thermalite Aircrete Shield - Forterra. The thinnest size is 50mm and it has a value of 3.6N/mm² 

 

I'm looking for a good compromise between price, being thin, possibly lightweight and moisture resistant and if possible with the higher N values (7N and upward)

Edited April 29, 2024 by MariaD

[Canski]

Once you go thinner than 100 mm the labour price will start to rise. thinner blocks are less stable during construction so they take longer to lay.

[Mike]

The quick answers are:

1 - If comparing blocks of similar density, yes. Otherwise no.

2 - No - standard blocks are more robust

3 - No - for airborne sound block density and thickness are the major factors. For impact sound, you either want a double wall or, on the other side, plasterboard on resilient bars / a fitted wardrobe.

 

29 minutes ago, MariaD said:

What is the thinnest block I could use for partition walls that has good sound insulation and is strong enough to hang cabinets on it?

A 100mm 3.5N dense or medium weight block is a good compromise, cheap and widely used.

 

Note  if you need to chase conduit into the wall, then vertical chases are limited to 1/3 of the wall thickness, and horizontal ones to 1/6 of the wall thickness - so the thinner the wall, the shallower the chases permitted. Which may or may not be a problem, depending on what you're planning.

 

[JohnMo]

1 hour ago, MariaD said:

thinnest for a partition wall in order to save money.

3x2 stud wall, with 12.5mm plasterboard each side, 95mm thick. 50mm high sound insulation.

[Iceverge]

@MariaD

 

What two rooms are you hoping to separate? 

 

What are you hoping to hang on the walls

[SteamyTea]

If it is a non structural wall i.e. not holding up a roof or ceiling, then it does not really matter.

Sound transmission is a different issue.

While density does help, it stops air movement via a damping effect, shape makes a difference as well, shape scatters, diffuses and causes interference to the returning pressure wave.

[MortarThePoint]

Use 100mm blocks. Lots of suppliers selling 75mm blocks for more than 100mm blocks. Higher strength blocks are more expensive so that's a factor. The 'stiffness' of any membrane goes with the cube of its thickness so a 75mm wall is massively weaker against lateral forces.

 

Cost - 100mm better

Sound - 100mm better

Strength - 100mm better

Giving back 25mm of room - 75mm better

 

I'm not sure I'd want to lean against a wall made of 50mm blocks.

[SteamyTea]

5 minutes ago, MortarThePoint said:

I'm not sure I'd want to lean against a wall made of 50mm blocks.

Depends how dense they are.

The lateral re4sistance of the wall is a function of the mass and gravity.

 

The one problem with block is that the catastrophic failure point is often lower than a timber stud wall.

 

 

 

Edited June 2, 2024 by SteamyTea

[MortarThePoint]

27 minutes ago, SteamyTea said:

The lateral re4sistance of the wall is a function of the mass and gravity.

Key factors for sure and any lateral force needs to first overcome the compressive force to start putting joints into tension. But not just mass and gravity. The narrower the footprint the easier it is to push over. Edge and top restraints would be key.

 

Another aspect is the allowed deviation of 8mm is 16% of a 50mm block width.

 

50mm Thermalite block looks to only weight 3kg so that's just 72kg plus mortar per m of wall which is comparable to my weight.

Edited June 2, 2024 by MortarThePoint

[SteamyTea]

26 minutes ago, MortarThePoint said:

that's just 72kg plus mortar per m of wall which is comparable to my weight.

You need to add the mass of 7 pints of strong ale to that, then you can fall over easier.

[saveasteading]

1 hour ago, MortarThePoint said:

I'm not sure I'd want to lean against a wall made of 50mm blocks.

I've seen such a wall in a London council flat. Hanging a kitchen unit on it was a bit scary, and you can't even use a long screw. The kitchen strengthened it.

We aren't getting responses from the the OP @MariaD so it's all academic.

[joe90]

Fitting a kitchen fir my sister years ago I discovered an internal wall was only about 3” thick it was noticed when rawlplugs for recessed sockets poked through the wall paper in the lounge 🙄.

[Mike]

12 hours ago, MortarThePoint said:

I'm not sure I'd want to lean against a wall made of 50mm blocks.

Don't come to France then! The old partitions in my place were built with 30mm thick bricks that look like thick terracotta tiles. The chimney still is, which is crazy.

 

Domestically 50mm or 75mm seems to be the norm here these days, and of course the sound resistance is hopeless, so there's a good market in upgrading them.