Cellular concrete is a
matter that is made of quartz sand or ash, cement, lime and water. The porous
structure is characteristic for aerated concrete, which it owes, among others good thermal insulation properties. What
should you pay attention to when choosing a suitable cellular concrete for
building walls?
Blocks are made of
aerated concrete. Their important parameter is the bulk density - depending on
it, the blocks are produced in several different varieties (with a density of
400, 500, 600, 700). The higher the density of aerated concrete, the higher is
its strength, but at the same time has lower thermal insulation.
Cellular concrete -
concrete grade and thermal insulation
The 500 or 600
cultivars, which are readily used for the construction of structural walls, are
characterized by high strength, however, they are not as warm as those
characterized by lower strength of the 400 modulus block. It is assumed that
class 400 blocks allow to obtain the U-value = 0. 18 W / (m2 · K), class 500 - U = 0. 20
W / (m2 · K), and class 600 - U =
0. 22 W /
(m2 · K). It must be remembered that the lower the permeation coefficient, the
better the material protects against heat losses.
For the construction of
sandwich walls insulated with mineral wool or polystyrene, class 500 and 600
cellular concrete are recommended, because thermal insulation of the wall is
largely due to the insulation material. Therefore, there is no need to use 400
blocks, which are great for single-layer walls. Unfortunately, the warmer the
cell block is, the generally worse it insulates acoustically.
Cellular concrete is a
vapor-permeable material that is easy to process - it can be cut and grinded,
practically to any shape. For this reason, cellular concrete blocks are readily
used in the construction of arched walls.
Cellular concrete and
wall thickness
Various blocks of
various dimensions are available on the market. This allows you to make the
optimal choice as to their thickness and length, so that masonry work can be
carried out efficiently, without additional investment. Single-layer walls are
usually built from 36. 5 or 48 cm thick blocks , in a double-layer wall the wall
usually has a thickness of 24-30 cm . For the construction of partition
walls, a cellular concrete with a smaller thickness, eg 6 or 12 cm, is used .
Forms and shapes
On the market, we find
blocks cut with less accuracy (marked with the GPLM symbol), intended for
bricklaying walls for a thick joint (ordinary mortar) and blocks cut on modern
slicers (marked with the TLMA symbol), which are coated with thin-layer
adhesive mortars. Cellular concrete, like hollow bricks, may have shorter sides
contoured for feathers and grooves. Thanks to that, they are bricked without
having to fill the joint with vertical mortar.
