Fir plywood is a composite building material made of thin layers of wood glued together, with at least a portion of the plies coming from spruce. Spruce wood is typically combined with other types of wood to create a stronger finished product for indoor use. Plywood is graded based on defects, with A being the highest and D being the lowest. Specialized types of spruce plywood include marine plywood, which is coated with resin but can suffer from control problems.
Fir plywood is a type of composite building material that is typically produced in sheets. It is made up of thin layers of wood, also known as veneers or layers, hence the name plywood. To be considered spruce plywood, at least a portion of the plies must come from a spruce. This often leads to plywood with spruce cores, or cores, covered with birch or other wood, but which are still known as spruce plywood. The veneers in a sheet of plywood are glued together and positioned so that the wood grain of each sheet is perpendicular to the adjacent sheet, leading to greater overall strength.
From the scientific family Pinaceae, fir is a type of evergreen conifer, meaning it has needles instead of leaves and stays green all year round. There are between 48 and 55 distinct species of fir trees, including Abies balsamea, which is the balsam fir, and Abies braseri, the Fraser fir. While similar in appearance and well known, Douglas fir is not actually a type of fir, as it belongs to a different genus, Pseudotsuga.
Spruce wood is not considered usable for general construction by itself. It is then typically combined with other types of wood to create a plywood that is both stiff and durable. It is also primarily meant for indoor use, as the fir does not have any insect or disease resistant properties once cut. Fir plywood is often used inside homes and for siding in home construction.
Plywood is considered engineered wood, as it is generally a composite of different types of wood. This combination usually leads to a stronger finished product. When a batch of plywood is produced, it generally receives a grade based on the amount of knots, splits, and other defects in the finished product. Each side of a plywood sheet can have a different grade: A is the highest grade and D is the lowest.
A typical size and quality of plywood may be listed as 3/4 AC, which means it is three-quarters of an inch (about 19mm) thick and one side is high quality, while the other is half to low quality. Plywood with a D grade will also sometimes be followed by the letter X. This generally means that it is intended for use on the exterior of a home or building and is meant to be glued down.
Specialized types of spruce plywood can include marine plywood, which is used in boat building. This type is coated with a resin and is of higher quality than that used in homes. However, spruce marine plywood often suffers from the control problem, which occurs when small cracks or hairlines appear in the wood due to exposure to the elements and the natural expansion and contraction of the wood. For this reason other woods, such as Meranti or Okume, are often preferred to spruce in boat building.
Protect your devices with Threat Protection by NordVPN
