An example of solid wood flooring, site finished with urethane

Wood flooring is any product manufactured from timber that is designed for use as flooring, either structural or aesthetic. Bamboo flooring is often considered a wood floor, although it is not manufactured from timber, but a grass.

[edit] Types

[edit] Solid

Solid hardwood floors come in a wide range of dimensions and styles, with each plank made of solid wood and milled from a single piece of timber. Solid hardwood floors were originally used for structural purposes, being installed perpendicular to the wooden support beams of a building. Modern construction techniques now rarely use wood building frames and solid hardwood floors are used almost exclusively for their appearance.

For flooring, solid wood has many limitations due to the natural characteristics of wood. Expansion and contraction of wood from moisture and temperature fluctuation puts many dimensional restrictions on solid wood floors. Typically, 5" wide and 3/4" thick boards are the largest that can be manufactured from solid wood without compromising the structure of the flooring (some manufacturers produce wider boards using proprietary milling techniques). There is, however, no standard size which will perform well in every environment. For contemporary construction techniques, the most significant characteristic of solid wood floors is that they are not recommended to be installed directly over concrete.

[edit] Engineered

Wood flooring is a popular feature in many houses.

Engineered wood flooring is comprised of two or more layers of wood in the form of a plank. The top layer (lamella) is the wood that is visible when the flooring is installed, and is adhered to the core (or sub-strait) which provides the stability.

Laminate, vinyl and veneer floors are often confused with engineered wood floors - laminate uses an image of wood on its surface, vinyl is plastic formed to look like wood, and veneer uses a thin layer of wood with a core that could be one of a number of different composite wood products (most commonly, high density fibreboard).

There are two different approaches to engineered wood flooring manufacturing:

1) Wood ply construction ("sandwich core"): Uses multiple thin plies of wood adhered together. The wood grain of each ply runs perpendicular to the ply below it. Stability is attained from using thin layers of wood that have little to no reaction to climatic change. The wood is further stabilized due to equal pressure being exerted lengthwise and widthwise from the plies running perpendicular to each other.

2) Finger core construction: Finger core engineered wood floors are made of small pieces of milled timber that run perpendicular to the top layer (lamella) of wood. They can be 2-ply or 3-ply, depending on their intended use. If it is three ply, the third ply is often plywood that runs parallel to the lamella. Stability is gained through the grains running perpendicular to each other, and the expansion and contraction of wood is reduced and relegated to the middle ply, stopping the floor from gapping or cupping.

Engineered wood is the most common type of wood flooring used globally. North America is the only continent that has a larger solid wood market than engineered, although engineered wood is quickly catching up in market share.

[edit] Comparison of Solid Wood and Engineered Wood

It is very difficult to compare a solid wood floor to engineered wood floors, as there is a wide range of engineered wood floor qualities. There are several limitations on solid hardwood that give it a more limited scope of use: solid wood should not be installed directly over concrete, should not be installed below grade (basements) and it should not be used with radiant floor heating. Solid hardwood is also typically limited in plank width and is more prone to gapping and cupping with increased plank size. Solid wood products, on average, have a thicker 'sandable area' (the wood that is above the tongue), and can be installed using nails. Lastly, solid wood tends to be less expensive than engineered wood, but this, as with the 'sandable area,' depends on the quality of the engineered wood (most inexpensive engineered wood products are 'veneer' wood floors, and not 'engineered').

Engineered wood flooring has several benefits over solid wood, beyond dimensional stability and universal use. Patented installation systems (such as "click" or "G6") allows for faster installation, and easy replacement of boards. Engineered wood can use 'floating' installations, further increasing ease of repair and reducing installation times.

[edit] Manufacturing

There are three ways engineered hardwood floors are manufactured.

[edit] Rotary-peel

This process involves treating the wood by boiling the log in water at a certain temperature for an allotted amount of time. Then after preparation the wood is peeled by a blade from the outside of the log, and it works its way around the log toward the center, creating a wood veneer. This veneer is then pressed flat with high pressure to make the veneer flat. This style of manufacturing tends to have problems with the wood cupping or curling back to its original shape. This problem is commonly known as "face checking" and is a manufacturing defect. Rotary-peeled engineered hardwoods tend to have a plywood appearance in the grain.

[edit] Sliced-peel

This process involves the same treatment process that the rotary peel uses. However instead of being sliced in a rotary fashion, this style of wood is sliced from the end of a log. From there it goes through the same manufacturing process as a rotary peeled product. However this style of engineered hardwood tends to have less problems with "face checking" and also does not have the same plywood appearance in the grain. However, this product can tend to have edge splintering and cracking due to the fact it has been submersed in water and then pressed flat.

[edit] Dry solid-sawn

Instead of boiling the hardwood logs, in this process they are kept at a low humidity level and dried slowly to keep moisture from inside of the wood cells. The manufacturing process to get this top veneer layer is similar to how a solid hardwood is manufactured. This style of engineered hardwood has the same look as solid hardwood, and does not have any of the potential problems of "face checking" that rotary- and slice-peel products have, because the product is not being exposed to added moisture.

[edit] Floor Finishing, Refinishing, and Sanding

Sanding provides a method for smoothing an installed floor, compensating for unevenness of the subfloor. Additionally, sanding is used to renew the appearance of older floors.Sanding using successively finer grades of sandpaper is required to ensure even stain penetration when stains are used, as well as to eliminate visible scratches from coarser sandpaper grades used initially. Prior to modern polyurethanes, oils and waxes were used in addition to stains to provide finishes. Beeswax and linseed oil, for example, are both natural crosslinking polymers are hardened over time. Modern polyurethanes, and polyester resins, used occasionally, are superior in toughness and durability.

[edit] Care of Wood Floors

Proper use of vacuuming, sweeping, and damp mopping is usually all that is required to maintain the cleanliness and appearance of a wood floor.We should not use oil soaps to clean the floors.The best suggestion is to use the manufacturers recommended cleaning products. Like tile floors, excessive grit and foot traffic will affect appearance. Unlike carpet or rugs, a properly finished wood floor, like tile, does not accumulate hidden soil or odorous compounds.

[edit] See also

• Reclaimed lumber
• Parquetry

[edit] External links

• National Wood Flooring Association (consumer site)