FLOOR LEVEL

In order to ensure a correct prepared surface for diamond grinding and polishing of a concrete floor, the accuracy of the floor need to be 3-5 mm and will be measured as described below. Method of Measurement of Deviations: a) Any deviation from flatness of a plane surface (floor) will be measured as the maximum deviation (3-5 mm) of the surface from any straight line of length 3 m joining two points on the surface, determined by means of a straight-edge the ends of which are supported on identical blocks of suitable thickness placed over each of the points. b) Any abrupt change in a continuous surface, including a local depression or peak in a floor or wall and any abrupt change caused by a joint in formwork will be measured as specified in (a) above. PLEASE NOTE: ALL OF THE ABOVE INFORMATION IS A GENERAL GUYED AND NOT SITE SPECIFIC. MORE INFORMATION REGARING THE SPECIFIC SITE SHOULD BE COMMUNICATED TO HAE FOR THE BEST FLOORING SULOTION.

FLOOR REQUIREMENTS

• All Concrete floors for Polished concrete to be at least 30MPa at 28 days. Tested to SANS 5863. Concrete strength below 30MPa cannot be grinded and polished. • The concrete floors for polished concrete should be levelled to Accuracy class I according to SANS 1200 clause 6.3.2. Floors that are not level needs to be grinded more and increase the grinding cost to get the floor acceptably level. • Aggregate size and type does not play a major role in the structural integrity while doing polished concrete (as long as the concrete is 30MPa), but the final outcome is influenced by the type of aggregate used. Because the aggregate are exposed after the floor has been grinded and polished. Fine aggregate (sand) should preferable be put through a sieve, where plant material is present, else you’ll find the plant material at the top of the floor. We then need to fill those openings and the colour of the grout can be different than the rest of the floor. • Surface beds should not be less than 100mm and we propose at least mesh ref 395 reinforcement being placed 30mm from the top, to prevent excessive cracking. As an alternative Fibre at 600g/m³ can be used. But crack prevention and handling depends on the Engineer’s design. HAE can assist with recommendations on specific floors. • Joints can be normal expansion or construction joints, with or without strips cast into the concrete and be sealed afterwards with a sealant. • Some HTC grinding machines work on 3 Phase electricity. The required power available should be 25kVA for the smaller machines and 70kVA (for machine and vacuum) for the bigger machines.

 PO Box 9622, Windhoek, Namibia  losch.heinz@gmail.com  +264 81 144 6969

NAMIBIA

POLISHED CONCRETE

A HTC SUPERFLOOR™ is a very cost-effective solution – for the short term, long term and everything in between. The cost per square meter is surprisingly low, since the concrete is usually already in place. But HTC Superfloor™ is also a smart alternative for new construction since grinding can begin just 5–7 days after casting. The fact that concrete is a tough and durable material has been common knowledge for thousands of years. Ancient traces of the material dating back some 7000 years have been discovered and some of the most famous buildings from the Roman Empire, including the Pantheon, were built of concrete. Yet in spite of this, knowledge of making concrete was forgotten. It wasn’t until the 17th century that concrete was rediscovered and once more became one of the most common construction materials of our time. HTC Superfloor™ is the revolutionary flooring concept with a technique that makes concrete more than just strong and hard-wearing. The technique is as simple as it is ingenious. HTC’s machines and diamond tools grind and polish concrete floors to remove the surface paste and expose the stronger concrete beneath. The result of this process is a stronger, more durable, shiny and beautiful floor. The environment and your bottom line both benefit too. When a concrete floor is cast the strongest material, the stone aggregate, settles below the surface leaving mainly cement at the upper surface. The HTC Superfloor process entails mechanically enhancing a newly cast or existing concrete floor. The concrete is ground step-by-step according to a well- defined process for achieving the desired characteristics.