TECHNICAL

Select a category below

01

Types of floor

There are a number of different types of products on the market, but they can all be grouped into three main categories: solid wood, multilayer or semi­solid wooden floors and engineered wood floors.


SOLID WOOD

Solid wood is one piece of wood all the way through from top to bottom, regardless of width or length. It can be bought unfinished or pre­finished. An unfinished wooden floor will need to be sanded after it has been installed to bring the surface of the floor to a level of smoothness that will accept a lacquer or oil. A pre­finished wood floor will normally have been treated in the factory with several coats of lacquer or oil. It can come in various lengths, shapes, dimensions, etc. The width of a solid floor will determine how the wood flooring is referred to. Narrow boards up to 90mm in width are generally referred to as "strip flooring", whereas boards wider than 90mm are referred to as "plank flooring". The same applies to the thickness of the floor; 18mm-22mm thick floors are generally referred to as "solid floors", and the thinner 10mm-­15mm floors as "overlays". Overlays and Solid wood floors are fitted in different ways. Solid floors have a tongue and a groove on opposite sides and ends of the boards which means they can be secretly nailed down to a suitable wooden sub floor, it is never recommended to glue down solid hardwood floors. Overlay floors are square shouldered and are exclusively face pinned and glued to a suitable wooden sub floor, usually plywood or chipboard. Industry standards state that a solid floor should be no more than 130mm wide (with no restrictions on length) unless face fixing is used to prevent the board from bowing or cupping. However, this is rarely adhered to by most companies, as the current trends are for long and wide planks.

MULTILAYER OR SEMI SOLID WOOD FLOORING

Multilayer floors are manufactured by bonding a hardwood veneer to a plywood base. Typical board dimensions are 140mm -300mm wide, 900mm-2700mm long and 16mm or 21mm thick. The 21mm thick multilayer floors are the most common and are manufactured by bonding a 6mm hardwood veneer to a 15mm plywood base. The 16mm floors are manufactured by bonding a 4mm hardwood veneer to a 12mm plywood base. 21Mm thick products are considered 'load bearing' and can therefore be fixed directly to existing floor joists in place of traditional pine floor boards. Ply backed multilayer floors are very stable. The hardwood veneers get their stability from the plywood base layer allowing them to be fitted as a floating floor on top of any compatible wood flooring underlay. They can also be nailed down like traditional solid wood floors or stuck down directly to the sub floor. This is very versatile product suitable for almost every hardwood flooring project. This product is not always suitable to be fitted with underfloor heating due to the difference in stability between the plywood base and the hardwood veneer make sure the product specified conforms to British Standard 8201:2011 before fitting over underfloor heating.

ENGINEERED WOOD FLOORING

Engineered wooden floors are a three layer construction. The top layer or the wear layer as it is known is the part of the wood floor that is seen and walked on and can be almost any hardwood or even a soft wood. This top layer is supported by and gets its stability from a core layer made up of strips of wood that run at 90 degrees to the top layer. The core layer is usually made from strips of fir but can also be hardwood. The whole board is completed with a balancing base layer of either fir or hardwood with the grain running in the same direction as the top layer. Typical board dimensions can be anywhere from 138mm-­400mm wide, 1200mm-­7500mm long and 9mm­-22mm thick. The 19mm-­22mm thick engineered floors are manufactured using the same principle described above. These products are considered “load bearing” and can therefore be fixed directly to existing floor joists in place of traditional pine wood floor boards. In most cases the thicker the engineered floor the thicker the veneer, veneers can range from 0.5mm-­6mm. The three layer construction of an engineered floor with the grain on each layer running at ninety degrees to the adjacent layer makes the board very stable thus allowing it to be fitted as a floating floor on top of one of any number of different underlays. Engineered wooden floors can also be stuck down directly to the sub floor. This kind of installation is in fact the recommended method when certain types of underfloor heating are being used. Engineered boards have a lower moisture content than solid or semi solid wood floors and are therefore more likely to conform to BS8201:2011 when it comes to fitting wooden floors over under floor heating.