Frequently Asked Questions:

Solid hardwood floors:

A solid traditional timber floor is still sought after by many. It is timber throughout the plank and has certain advantages: it generally offers more flexibility when installing (as the installer can machine timber profiles for joints, makeup stair treads, profiles and skirting to match), and the choice of sealant can be decided after the installation. It is also arguably easier to repair a solid timber floor and, as there is generally more timber above the tongue, should last longer.

Solid wood, however, is a lot less stable than engineered flooring when installed. More care and expertise is required for the installation. Thus a solid timber floor is generally more susceptible to moisture issues and will misbehave if exposed to moisture.

With solid timber floors, a much stronger adhesive (Wakol MS 230) and a very good moisture barrier (Wakol PU 280) is required, to hold the floor in place and to prevent excessive movement. It is not recommended to install solid timber above under-floor heating, and even then gaps of up to 2-3mm can be deemed as normal in a solid timber floor with or without underfloor heating.

More recently there have been serious innovations made with solid layered engineered flooring. This product comprises of three layers of solid wood cross-laminated for amazing stability. The Planca range which is represented by Zimbo's Flooring Solutions in South Africa is of this design, and allows for 300mm to 400mm widths in solid Oak and Ash for the most extreme wide floorboards, and is also suitable with underfloor heating.

Engineered hardwood floors:

Engineered hardwood flooring is typically a product made up of a core of hardwood, plywood or HDF and a top layer of hardwood veneer that is glued on the top surface of the core and is available in almost any hardwood species. The product thus has the natural characteristics of the selected wood species as opposed to a photographic layer on plastic (laminate flooring).

The "engineered" product has been designed to provide greater stability, particularly where moisture or heat pose problems for solid hardwood floors. Engineered flooring is now the most commonly used hardwood flooring product across the globe.

Generally, the engineered floorboard will have either a three-ply base (made of poplar and pine) or a multiply base which is typically made of birch. The latter product is probably more stable, however, a good quality three-ply floor installed correctly is every bit as a good as a multilayer floor. In the case of the Planca engineered range, the engineered version has a quarter sawn pine core for extra stability.

Engineered flooring (when glued down) can also be installed over underfloor heating that has been cut into the screed, or the water pipe version. Certainly in any situation where moisture is an issue such as a bathroom or kitchen, the multilayer floor would be the first preference. Also, since the hardwood layer is only a few millimetres in thickness, a lot of hardwood is saved by going for this option. Thus it certainly is the more environmentally friendly option.

Laying solid timber flooring above underfloor heating is not generally recommended unless it is a product like the Planca range, as the construction prevents excessive movement that is induced through the heating of the timber. Even then 2mm gaps between boards can develop due to the timber drying out, and would be deemed normal in this installation.

Engineered flooring would be the preferred product for installations above underfloor heating. An important fact to remember is that due to the thickness of timber flooring (15mm - 20mm normally), it takes a substantial amount of time for the heat to transfer through the floor. Thus the underfloor heating needs to be turned on and left on for a few days before the heat will be felt on the surface.

Underfloor heating needs to be regulated to no more than 27 degrees Celcius, and any temperature changes made, should be done in small increments over a few days. To minimise the movement of solid timber floors above underfloor heating, humidity/climate controls should be installed.

To maximize the durability and beauty of your hardwood flooring, we recommend the following practices as part of your floor's normal care and maintenance.

  • Place doormats or rugs at entrances to collect moisture, sand, grit and other potentially damaging substances from being tracked onto your hardwood floor.
  • Dust mop or vacuum with a soft accessory to keep your hardwood floor clean from dust, dirt or grit. Hardwood flooring cleans easily with a dry mop.
  • Purchase all cleaning material from the site, and use the Loba cleaner and other maintenance products which are Ph neutral for maintenance on the floors. Loba has a wide range of products for both varnished and oiled floors.
  • Do not use harsh detergents, abrasive cleansers, or corrosive chemicals to clean your floor, only Loba products.
  • Avoid excessive water. Use mats in the kitchen, bathroom and laundry room to protect against spills. If a spill occurs, blot it up immediately with a dry cloth or slightly damp mop.
  • Use only colourfast and non-scratch carpeting or pads on your hardwood floor.
  • Protect the floor from furniture legs using floor protectors and do not walk on the floor with high-heeled shoes.
  • Although hardwood flooring has effective UV inhibitors in its pre-finish, it is recommended that it not be exposed to direct sunlight for long periods.

A pre-finished floor is a floor that has the coating applied off-site. This can be done in several different ways.

Most commonly the pre-finished flooring imported into South Africa has a U.V. coating applied in a factory environment, and this is very difficult to repair and match the floor if the floor is scratched or damaged.

Alternatively, the floor is pre-finished using natural oils or water-based varnishes which are products that air dry. The advantages of this system are that the floor can be easily repaired, and skirting and timber profiles can be coated to match the floor. Zimbo's Trading uses Loba quality coatings from Germany to pre-finish all their pre-finished flooring.

Unfinished flooring is flooring that is installed raw and is then coated on site after sanding the floor down. The advantages of this system are that one can fill the floor before a coating which in the case of a solid floor is advantageous, and then the floor joints will also get sealed with either the oil or water-based varnish, which prevents moisture from going between the boards.

A nail down floor is generally installed on timber batons fixed to the concrete subfloor, using the secret nailing method to fasten the floor through the tongue to the baton. This traditional method allows for a cavity space between the floor and the concrete, but should not be installed above bare earth, as was the practice when our grandparents were growing up! Times have changed, and modern kiln dried flooring does not allow for the moisture that rises from the earth, even if the floor is vented on the sides.

The nail down floor is noisier when walking on it, and gives a traditional feel, that is sought by many. The glue down floor is cheaper to install, as there is no construction of the substructure required. What is critical is the quality of the concrete screed and the fact that this is level. The floor follows the level of the concrete screed, and thus adjustments in height cannot be made as with a nail down. The glue down is also very quiet to walk on and gives a wonderfully solid feel underfoot. The glued down floor is the most commonly used installation method, is best used where height presents a problem in existing or new homes, or where a quick installation is required.

A floating installation is the cheapest method of installing a wooden floor, and normally comprises a plastic layer with foam (combilay) laid onto the screed and then the floor is fitted above this. The floor is normally glued in the tongue and groove joint. The issue with a floating floor is that there is a lot of noise off of the surface with heels or hard shoes, and the floor tends to mover underfoot. There are also restrictions on how wide you can install the floor without an expansion joint, as the floor tends to have a lot of movement.

With all 3 applications, a moisture test of the concrete screed is essential before the installation of the wooden floor, one cannot tell by looking at a screed as to the moisture content! Also, a moisture barrier is required for all ground floor installations, and care should be taken before the installation to ensure that all sliding doors, windows etc, have been correctly waterproofed. No timber floor likes moisture from below, and cupping and delamination will occur if substantial amounts of moisture are trapped between the floor and the concrete.