ᐅ Exterior walls made of solid clay blocks, interior walls of 11.5 cm lightweight concrete blocks

Hello,

Could someone please tell me if it is possible to use 11.5cm (4.5 inches) calcium silicate blocks for the interior walls on the upper floor when using 17.5cm (7 inches) Poroton plan bricks for the exterior walls? Or are there any complications to consider in any regard? I would prefer to have 11.5cm (4.5 inches) calcium silicate blocks as partition walls upstairs because they provide better sound insulation.

Regards

MaB

Hello,

MaB schrieb:

Can someone possibly tell me if it is okay to use 11.5cm (4.5 inches) calcium silicate bricks for interior walls on the upper floor when using 17.5cm (7 inches) Poroton planning bricks for the exterior walls?

Cracks may occur because the bricks have different shrinkage behaviors. This means cracks can appear at the joints between the calcium silicate bricks and Poroton bricks, especially at vertical wall corners where the interior calcium silicate wall meets the exterior Poroton wall. The cracks can show up as late as five years after construction; it takes that long for everything to settle.

This can be prevented, but it requires the plasterer to apply rebate cuts in the corners. In this case, the plaster on the Poroton wall is separated from the plaster on the calcium silicate wall by a thin gap, preventing the plaster from cracking there.

This practice is also common where chimney shafts connect to the walls behind them during construction. If the plasterer works carefully, it is usually not an issue.

As an alternative, lightweight partition walls are also a good option; they offer excellent sound insulation and are much better than their reputation suggests.

Regards, Bauexperte