One of the earliest developed thresholds, the wood is used today for a variety of reasons. In addition to its aesthetic values, energy efficiency is increased because wood has a lower heat transfer coefficient that aluminum. Ease of installation is a bonus for this product and it also prevents moisture and frost from forming on the inside of the threshold when outside temperatures are low and inside conditions are warm and humid. Wood thresholds are often stained before installation and come unfinished. M-D Building Products produces a variety of wood thresholds to fit any application.