Plywood basically is a sheet of wood, which is made from thin piles of wood veneer that are glued together under pressure. Plywood binds wood fiber sheets and resin to form a complex material. While making the sheets, the wood grains are alternated to ensure that the wood does not split when worked on. In addition, graining plays an important role in limiting shrinkage and expansion, enhance dimensional stability and more.
It is worth noting that plywood comes in different sizes. In the local stores, you can find softwood and hardwood plywood that are sold as 4-feet wide, or sometimes available in 2 and 5 feet widths respectively.
Typically, the common lengths are 4, 8, and 12 feet sheets. At best, many people understand the width and length measurements, however, the thickness dimensions have been found to puzzle majority of the people. In the United States, the most well-known plywood sizes are 1/4″, fir and 3/4. Sometimes the thickness dimensions can be written differently. For example, 1/4″, fir, and 3/4″ are tagged as 7/32, 15/32 and 23/32 respectively.
Plywood Grades and Features
Ranging from sanded smooth to gaping spaces around cracks as well as knots, every grade of veneer has varying characteristics. The US has about 4 basic softwood grades labeled A, B, C, and D. In some cases you may come across the fifth grade popularly known as C-Plugged. Interestingly, each and every sheet features 2 grades, such as AD or BC. The first letter represents the front veneer and the second letter indicates the rear veneer. Other plywood sheets have a third letter ,X, which implies that the sheets are ideal for external USG.
What to Look for When Choosing the Grades
The above grade is sanded smooth and paintable. What make this grade stand out is that they are easily available and free of knots.
This grade comes with a solid surface that needs some few repairs since it usually have tight knots and minor splits, but with no chunks of wood missing.
Generally, the grade is characterized by tight knots measuring about 1′, and knotholes up tot’. It also has some splits and discoloration that lower the quality of veneer.
Some of the characteristics of this grade include knotholes and knots of up to Yin diameter. However, the splits and knots found on this grade do not require any repairs.
Types of Plywood
In the market today, you will come across an array of plywood types, including interior plywood, exterior plywood, structural plywood, and marine plywood.
The exterior plywood is suitable for exterior use due to the fact that the material used to make it moisture resistant. It is also available in a wide range of grades. But the most popular grade in this category is COX plywood, which is widely used for most common construction in stores and centers.
Are you looking for the strongest plywood for internal and external purposes? If yes, then get structural plywood and you will never regret. Some of the grades under this category include CO and OD.
If you want to construct things inside the house, then interior plywood is your ideal choice. Only use this sheet within the house since it is not suitable for harsh elements of weather. Here you will get various grades, such as AC, BO and so on.