Getting the Best Results from your Blocks

DO NOT WET BLOCKS

ACT Masonry blocks should be dry when laid in the wall to minimise subsequent shrinkage.

Cleaning Concrete Masonry

Keep mortar off the face of the blocks. Clean off droppings as work progresses and before mortar sets.

Cleaning down with acid should be avoided where possible.

A guide to cleaning concrete masonry is available at ACT Masonry or full technical details are available from the Concrete Masonry Association website - www.cmaa.com.au

Colour

Care should be taken to order enough product to complete the project at the same time to avoid the possibility of batch variations.

Control of Shrinkage Cracking

ACT masonry blocks behave differently to clay brick in regard to moisture movement and temperature chamges. Assuming sound foundations are provided, cracks in walls cna be avoided by the correct use of control joints, bond beams and/or joint reinforcment. Rules for the use of thee lements are contained in Australian Standard 3700-2001 (put a link in?)

Useful estimating data

Blocks with 390 x 190mm face = 12.5 units per 1 square metre
To fill 200mm bond beams allow .013m³ of concrete per lineal metre of beam
To core fill 150mm 'H' blocks allow .65m³ of concrete per 100 blocks.
To core fill 200mm blocks allow .8m³ of concrete per 100 blocks.
To core fill 200mm 'H' blocks allow .84m³ of concrete per 100 blocks.

To core fill 300mm blocks allow 1.1m³ of concrete per 100 blocks.
To core fill 300mm 'H' blocks allow 1.32m³ of concrete per 100 blocks.

Water Thickner referred to in this table is methyl cellulose