Gone are the days of grey, dull concrete for indoor floor slabs. Today, concrete floors are awash with colours and decorative features. Stephanie McDonald reports on concrete colouring.
Concrete staining is growing in popularity as a decorative feature for indoor and outdoor flooring. It can be used by companies to emblazon their logo on concrete floor slabs or by clients wishing to create a unique feature on the floor.
Adding colour to concrete floors can be done via two methods — mixing colour into the concrete mix for new floors or staining the top of the concrete for existing floors.
Concrete Colour Systems supplies pre-coloured concrete and staining products. Kim Runje, sales manager at Concrete Colour Systems, says this is a popular way to decorate new floors as the costs are minimal due to the pigment being added before it is laid.
“The use of this style of coloured concrete is fairly flexible and can be used in many different ways, such as the placement of waves of colour, texture, shot blasting and logos or artwork can be added after curing with stains/dyes,” she says.
Runje says concrete stains applied to existing concrete floors range from acid-based stains to acrylic and water- based stains. “Acrylic-based or water- based stains can be referred to as dyes. We use only water-based stains as we are conscious of environmental issues,” she says.
“We endeavour to implement decorative mediums that can be used in all applications of decorative finishing, including Green Star projects. Stains/dyes are artistic based and are unlimited in the usages as it will always depend on the ability of the applicator.”
For Concrete Colour Systems’ staining products for existing floors, a topper is usually applied to the area — it chooses to use Stye pave cement- based toppers. The area then needs to be clean, dry and free from contaminates prior to applying the cement-based topper.
“Stains/dyes are then passed over the surface to give the coated area the depth or multi-tonal finish required. It can be applied with pump sprayers, airless sprayers, sponged on or poured on the surface and moved around with squeegees. For intricate areas paint brushes are used,” Runje says.
The toppers can also be trowelled down to replicate other materials, such as wood panels, tiles or slate. If a textured or multi-tonal finish is required, the topper is trowelled in the desired fashion and a first coat of stain/dye is passed over the finish. Once it is dried, a secondary colour can then be passed and so on.
“The benefits of using stains/dyes is that intricate artwork can be achieved and designs are limited only by costs and the ability of the applicator. Stains and dyes can be used anywhere concrete is currently laid — internal, external, domestic or commercial. However, these finishes are traditionally used internally and in areas that are usually tiled.”
Runje warns artistic finishes will cost more and charge a ‘project’ cost as opposed to a per sqm cost. She says this is due to the complexity and the time required to create the finish.
“If logos and artwork are required, all lines need to be 9 inches [in the] ground or scribed into the surface, so the applier needs to endeavour to keep lines clean to ensure that colours do not bleed into one another. Always remember that this is not a manufactured finish, so some variances in colour or texture will occur,” she says.
Designer Concrete Coating’s stain product is an acid-based mineral salt-colouring agent. The product has been designed to simulate the decorative features and colours of weathered stone, terrazzo and quarried tile finishes.
“Decorative effects can be achieved using a variety of techniques, including polishing, saw- cutting, pattern stamping, sand-blast texturing, overlay resurfacing and customising to produce originality in design and colour on interior floors or a unique look to residential driveways or entertainment areas,” says Kylie Bull, sales co-ordinator at Designer Concrete Coatings.
Designer Concrete Stain relies on a chain of chemical reactions. “The ‘acid’ in the stain opens the hardened concrete surface in order for the ‘metallic salts’ to reach the free lime deposits within the concrete,” Bull says.
Water from the stain solution fuels the reaction for a maximum period of four hours to yield insoluble coloured compounds.
Designer Concrete Stain can be sprayed on, brushed on or mopped, with the method of application determined by the design and finished surface effects required. It is also compatible with in-concrete radiant floor heating and concrete slab-on-ground passive solar designs.
Bull says prior to staining, the concrete surface must be cleaned and free of any contaminants. Existing slabs must have prior surface sealers or polishes completely removed. The slab must then have a commercial grade protective sealant applied to clear polyurethanes for exterior applications or water-based epoxy for interior applications.
The advantage of concrete colouring is no two concrete slabs will ever be the same as each slab accepts staining in various degrees.
Stained finishes are also permanent, but Runje cautions an update of the sealing coating is imperative to ensure artwork retains its integrity. She says “ensuring that the protective coating is maintained will ensure that the artwork or decorative finish will not be damaged or fade.”
