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Coloured Concrete

Coloured concrete's a popular choice for entertaining and pavement areas as well as internal floors. With the large range of colours available these days, we can help you select a product to compliment your indoor / outdoor area.

 

About the process

Coloured concrete is achieved by adding “oxides” to the concrete. These “oxides” are typically dosed either by kg/m3 or as a percentage of the cement content of the mix. They are added at the time of mixing your concrete, colouring the entire batch of concrete.

 

Important points

The finished colour of your concrete will always have variations giving a “mottled” appearance due to the different curing and finishing methods. Initially the concrete will appear very dark in colour (first 24-48 hours) and will lighten in small areas initially expanding until the entire area has dried evenly (about three months). Talk to your concrete contractor about the type of finish required prior to commencing the job i.e. broomed, machined, swirled mag finish, lightly trowelled or acid washed etc… to avoid any surprises on the day. Try to arrange the delivery of your concrete to avoid small loads, for example an area of 56m2 at 100mm thick will require a nett volume of 5.6m3, order say 6.0m3 to ensure you don’t run short but try to have the loads delivered in two 3.0m3 loads rather than a 5.0m3 load followed by a 1.0m3 load to ensure the colour is consistent. Curing (prevention of moisture loss) of the concrete is always important, but more so with coloured concrete. The best method is continuous water curing for at least four days, this helps avoid cracking, helps the concrete attain its potential strength and avoids dusting of the surface of the concrete.

 

Always remember

As with any concrete project the same basic principals apply which are; well compacted base course (dampened prior to placement), well positioned reinforcement (if mesh is used), sensible concrete thickness (we recommend 100mm min. for residential works), consistent water curing as soon as possible, well positioned joints (tooled joints may be required at high risk areas), saw cutting as soon as is practical.

 

Concrete cutting, acid washing and sealing

Saw cutting into squares of 1.0-1.6m greatly enhances the appearance of coloured concrete pavements, acid washing will remove the fine cement slurry from the surface of the concrete providing a fine “sandpaper” textured finish providing more grip but will also darken the concrete colour so take this into account when choosing your colour. Sealing the surface of your new exposed aggregate concrete will prevent staining and will enhance the natural beauty of the aggregate by giving it that “wet

 look” appearance.

 

 

Counties Ready Mix Ltd | Phone: 09 2946222 | Fax: 09 2946333 | email: info@crml.co.nz | PO Box 471, Drury, 2247

Physical address: 14 Bremner Road, Drury, Auckland, New Zealand | Google map link