Five years ago, Polished Concrete Ltd. earned our Commercial Polished Concrete Award using Husqvarna’s Hiperfloor, Premium finish, to deliver a stunning floor for a bank that added black oxide to the concrete mix to make New Zealand’s tan stone and white quartz aggregate pop. Since then, the country’s largest concrete grinding company has perfected its own polishing system to deliver yet another award-winning project.

Developed by Polished Concrete Ltd.’s Director Jason Torbet, Megafloor offers four aggregate exposure levels ranging from Warehouse at zero exposure to High Street, a 3mm-to-5mm grind. Three finishes – Standard, Classic, and Premium – allow for gloss-level options. Like ASB Bank in 2013, New Zealand’s high-end FreshChoice supermarket sought to stand out from the competition with a sleek black floor. The client chose the heavy-exposure High Street in the 3,000-grit Premium finish, which is the most scratch-resistant.

“Black floors require extra attention to detail,” says National Sales Manager Scott McBreen. “Like anything black, they show scratches more than other colors. To achieve best results, we bring the floor up very slowly with progressively finer diamonds. We do extra passes on some grits, and the use of lithium densifier ‘lick’ coats adds extra gloss points.”

Planning Ahead Pays Off

Delivering an unblemished floor was complicated by the need to protect the surface after removing 5 mm so other trades could begin work. Polished Concrete consulted extensively with the general contractor and client during the design phase to finalize staging as well as mix design and slab design, grinding methodologies, and procedures to protect the slab during construction. The company recommended a 30MPa (4,000 psi) mix and seven days of curing.

The team also was able to identify methods and materials that saved money and ensured FreshChoice would get just what it asked for.

Polished Concrete used Mega Diamond Tools tooling and chemicals along with Husqvarna grinding machines. The aggregate was initially exposed using 30-grit steel bond diamonds followed by a 60-grit cut to remove scratches. MegaFill was used with 160-grit diamonds to liquid grout and fill pinholes. MegaHard Potassium densifier was then applied and left on overnight.

After removing 5 mm, Polished Concrete applied MegaBoard breathable floor protection, which has a built-in spill guard.

Polished Concrete returned to the floor when construction was almost finished for resin polishing, starting with a double pass with 50 grit and 100 grit followed by a fine mist coat of MegaHard Lithium. Two more passes, with 200 grit and 400 grit, were made and followed by a coat of MegaHard Lithium. The floor was finished with 800-grit diamonds followed by two coats of MegaGuard, a penetrating stain protector. The surface was finished off by burnishing with brown pads.

Taking a Successful System ‘Public’

Jason Torbet launched Polished Concrete more than two decades ago. After five years of testing Megafloor, he’s preparing to offer the system to contractors that have successfully completed a rigorous training regimen using the company’s tooling and liquids.

“We’ve had rapid growth over the last 18 months, so we’re going to open it up to a select group as part of our strategic plan,” he says. “It’s important to keep a very tight rein on the number of approved contractors so we can manage quality control and protect the brand’s worth. Like every good system, there’s a strict process to follow to achieve that ‘X factor’ everyone’s looking for.”