Three common methods used for installing wood floors

 Nailing, Gluing and Floating.

Nail Down

This is the most common installation method. In this process the floor gets nailed or stapled directly to a wood sub floor.  The flooring is installed by blind nailing the material through the tongue of the floor board into the wooden sub floor.  This allows for the nails to be hidden and are not to be visible once the the floor is installed. This installation method works for both solid and engineered wood flooring on wooden sub floors.
It’s worth mentioning that if you do not use the proper amount of nails during this process, then squeaking or cracking is likely to occur. While using more fasteners than recommended could result in splitting the tongue.

Glue Down

This method involves using an adhesive to adhere the flooring material to the sub floor, or to a moisture barrier directly on the sub floor. The adhesives work by creating a bond between the sub floor and the wood flooring.  There are three basic types of wood flooring adhesives to choose from. The first is a water based, next a solvent based and finally a moisture curing urethane adhesive. Before you begin it’s important to make sure that the sub floor material is dry and most important, level. Should you find high and low spots you will need to make them level before installations begins.It’s important to only use as much adhesive as you can effectively work with in a 15 time period.  Any longer and installation may fail. With many adhesives, the adhesive material needs flash time to be affective. This is for optimal performance.

Floating

And finally we look at the floating  method. This process is over 60 years old.  Using this installation method, the flooring material is actually floated above it. Before beginning, check the levelness of the floor and if  it’s dry. In addition use a moisture and sound barrier Underlayment. Make sure that the Underlayment used wraps up the wall to completely encapsulate the flooring. Then when the last board is put in place, trim off the excess Underlayment.