Pre-finished solid hardwood flooring comes delivered with the finish already applied.  Factory applied finishes are mostly UV cured and contain Aluminum oxide which adds strength to the product. This is why most prefinished products come with 25 year finish wear through warranties.

Unfinished solid hardwood flooring, the traditional alternative to pre-finished, can be nailed to plywood and in some cases, glued to concrete sub-floors. Unfinished, solid hardwood flooring requires sanding and finishing onsite.  This is the more expensive choice, as the job takes longer to complete due to the sanding process but the end result is a more authentic looking product. In addition, a stain colour can sampled on the wood floor during the sanding process and adjusted to your preference.

What type of wood grain? There are a variety of grain options to choose from. Click here for an example of different wood grains.

Nail-down solid wood flooring has been the industry standard in North America since the hardwood flooring industry began.  If you have a plywood sub-floor and the space you want to install in is over top of a heated, enclosed area (not over a car port for example) then a nail down floor is recommended. 

Solid hardwood floors are dimensionally less stable than engineered floors. This means that they are more likely to shrink, expand or cup (curl) in reaction to changes in home humidity.  Humidity levels are unstable below ground level hence solid wood flooring is not recommended for below grade applications.

Some solid wood floor products do not suit every situation.
Solid wood flooring should not be installed below ground level.

Consult an expert before buying wood flooring for installation over in floor heating.