About Shamrock
Understanding moisture content and its effect on wood is extremely important. Misinformation on moisture results in more customer dissatisfaction than any other complaint.
When the first board is cut from a fresh log, it contains at least as much water by weight as the wood fiber itself. At that point, the board has 50%+ moisture content. If this lumber were to be placed on drying sticks and left to dry without any assistance such as additional heat or air flow it would dry to 16%-18% after 1 year. It would never dry to a lower moisture content. Modern kiln drying techniques can dry lumber to much lower percentages. Properly kiln dried hardwood lumber has a moisture content of 6%-8%. This must be equalized moisture content. When lumber is dried, heat and airflow are combined to force most of the moisture (water) from it. This is a very unnatural thing to do to lumber and can result in several defects in dry lumber that may not be noticeable to an untrained eye or a simple surface moisture test. Properly dried oak, for example, is actually over-dried on the exterior to well below 6%. It is difficult to remove enough moisture from the very core of the wood. It is dried below 6% on the exterior (shell) and allowed to equalize on the final kiln cycle. The interior (core) is actually 10%-12% moisture and will "wick" its' moisture to the shell which may be close to 0% under kiln conditions. If this core moisture is not properly equalized in the kiln, it will result in wood that twists and bows when milled. It will also eventually equalize which will allow additional shrinkage from lumber that tested 6%. If this core moisture is forced from the interior too quickly, the board will show "checking" or fiber separation that is caused when moisture in the form of water vapor literally "blows" its own path through the board.
With the lumber properly dried to 6%-8%, milled flooring products are a sponge just waiting for moisture. If we take that same kiln dried lumber and set it in an unheated area for 1 year, it will increase its moisture content to around 10%. It will also add 5% back to its dried width. If it is left in a home with no regard to relative humidity conditions, it will swell to 10%-12% during summer and fall conditions or can actually drop below 6% and shrink during extremely low winter humidity conditions. A homeowner's long term satisfaction with wood flooring depends on their willingness to seasonally humidify and de-humidify their home. The addition of a whole house dehumidifier or air conditioning for mid/late summer and fall will help keep a home from building up excessive moisture not only in the hardwood flooring, but within the walls and ceilings as well. Maintaining a home at 45%-65% relative humidity will help assure the minimum amount of movement due to the floors moisture content.
Due to the unique nature and blend of natural characteristics found in Shamrock Plank Flooring, it is suggested by the manufacturer that it be installed by a professional flooring contractor or a craftsperson that is experienced in the natural blends present in hardwood products.
