Since the appearance of the first lofts, concrete floors have gained popularity in the residential environment in Quebec. Today, they are not only prized, but lustrous. Some are even shiny like mirrors.
“Polished concrete has a great visual richness, because it highlights all the nuances of the material,” explains Montreal architect Henri Cleinge, who has always had a penchant for natural concrete without coloring. “Unlike ceramic,” he continues, “concrete lacks multiple joints and imposes itself as a large, uniform and stripped surface.”
“The majority of our customers prefer polishing at a gloss level,” said Kathleen Bélanger, vice-president of Béton Prestige. The demand for semi-gloss comes in second position and the rest of its clientele (around 10%) wants either a satin look, for an industrial style or, on the contrary, a very glossy level of polishing, mirror effect.
To the eye, however, it would be difficult to distinguish between “lustrous” and “very lustrous” polishings, according to Kathleen Bélanger. But this last finish would allow the concrete to preserve its shine longer.
“The higher the number of polishing steps, the denser and lustrous the concrete,” she says. Polishing in itself constitutes the floor covering. During the work, a liquid hardener is added to close the pores of the concrete and make it harder. As a bonus, it will no longer produce dust. At the end of the operation, a waterproof sealant can be applied, ”she summarizes.
Polish or vitrify?
In addition to polishing, it is possible to vitrify the concrete, that is to say to coat it with polyurethane. Alain Michaud, president of SAM Surface Preparation, proposes the two methods. “Polished concrete is less scratched because it is very hard,” notes the specialist. However, such concrete, even very dense, absorbs liquids. A waterproof sealant can only delay full absorption and provide more time for occupants to wipe the stain. Otherwise, if you wait too long, the concrete will be marked forever. ”
Conversely, concrete coated with polyurethane, satin or glossy effect, resists stains. “But it can get scratched if you drop a heavy object or if you move furniture with metal legs,” admits Alain Michaud. And will the sun make it yellow? “Not necessarily, because we opt for a polyurethane which includes protection against ultra-violet rays”, replies Mr. Michaud who adds, in the same breath: “Every three or four years, it is desirable to carry out a light sanding and applying a new layer of polyurethane to restore luster to the floor. “
> For 1000 ft2 of surface to be polished, dust-free, it takes about $ 8 to $ 10 per ft2, including finishing near the walls, at Béton Prestige.
> Vitrifying a new concrete surface of 1000 ft2 with two layers of polyurethane with UV protection costs about $ 4 per ft2, at SAM Surface Preparation. As for the price of a polishing (dust-free), it is around $ 8 per square foot, including finishing near the walls.