We recommend the use of 25mpa. Concrete for allwalls.

They can be hand filled in stages or pumped up to 2.5mts. high in one application.

Pumping the 250mm blocks requires a dryer mix as concrete when too wet can cause possible blowouts. Filling the 125mm blocks requires a wetter mix because of the narrower openings in these blocks.

A line pump with a 50mm hose outlet is best for pumping; slow and steady is needed for successful pumping.

We suggest that the first two courses of blocks (500mm) be hand filled, this is the time to get them level and straight. If you get this level correct it will eliminate troubles for the rest of the walls.

In these 2 course can be added to the concrete or if 35mpa concrete is used in these courses it is considered to be waterproof.

Using a 'vibrator' on the walls is not required or recommended just patting the walls with your hands is to be sufficient to make sure that the cavities are completely filled.

Windows and doorways can be placed in position at this stage and braced back. The blocks can then be placed around these items and then filled.

Builders often prefer to leave the windows out until the walls are complete and the roof is on, so they leave the appropriate openings in the walls.

In the case of 'FIRERATING WALLS', no polystyrene blocks can be firerated because of the polystyrene bridges that secure one side of the block to the other. To achieve a 'FIRERATING', our blocks when used in such a situation as a party wall between units, we either remove the bridges and fill the holes with mortar to produce a solid concrete core, or rely on 16mm 'FIRERATED' plasterboard fixed to both sides of the wall.
Manufacturers of 'FIRERATED' plasterboards should be consulted as to the duration of
the firerating.