There are different types of plywood, and they all come along with various features that are suitable for different purposes. That is why you cannot use all types of plywood when it comes to exterior constructions. You have to find the suitable features that will fit the conditions to which the plywood would be exposed. So, which plywood is best for exterior use, and what features should you look for?
Constructions that will be installed outside, or will be exposed to weather changes and conditions in any way, need a solid, thick and durable type of plywood. Usually, the best options in these cases are marine-grade plywood or ACX since they are known to withstand atmospheric changes.
Choosing the right plywood for outside constructions can be difficult, considering that there are a lot of factors that need to be taken into consideration. To make things easier for you, I have included all the necessary information related to plywood suitable for exterior use. So, this way, you will get familiar with what to look for in plywood for outside constructions, and you will make your pick with ease.
Which Type Of Plywood Is The Most Suitable For Exterior Use?
When it comes to choosing plywood for exterior constructions, you might hit a point where you will not know which type to pick. It is understandable since there are different types, and you never know what will actually work in your case. However, some things will help you make your choice, and you just have to familiarize yourself with the properties of the wood you intend to use.
Therefore, for wood constructions planned for outside, you need a solid and durable type of wood that will withstand the weather changes and conditions and not lose its shape with time. When choosing plywood, you need to consider its thickness, waterproof and water-resistance features, and the glue used in making a particular type of plywood. The best types suitable for exterior use are ACX and marine-grade plywood since they include waterproof permanent phenolic (WBP) glue in their content.
However, certain differences occur among these types of plywood even though they are all suitable for exterior use. These differences could be of crucial importance to you depending on what you intend to use them for. So, this is the reason why you cannot opt for the first type of plywood that comes into your hands labeled with exterior use features.
ACX Plywood
You can easily differentiate plywood because it is marked with letters. Those letter markings refer to the plywood features, and being familiar with the meaning of the letters can help you determine what type of plywood you need.
Therefore, the “A” in ACX stands for the front of the plywood and denotes that it is made of the highest grade. This means that the front is smooth and paintable, so it would look nice from the outside if you are concerned about the design. This type of plywood is usually free of knots and major repairs, so it is generally acceptable, and you will not have to worry about making it prettier on the outside.
The second letter “C” in ACX is related to the back of the plywood, and it denotes that the back is of a lower grade. When there is a sign of a lower grade, you should expect some defects on the back of the plywood. The thickness of the veneers on the back can be weaker for cost-efficiency purposes.
You can also expect some knots due to the lower grade, and you might also notice some discoloration and some splits. This is completely normal and widely known among builders, so if it is your first time working with plywood, do not get alarmed. This is the back of the plywood, so it will not be noticeable after the installation.
What is distinguishable about ACX is the core layer which includes several pieces of core veneers. Also, both joint and edge and edge joints might be present. These give stability to the plywood and make them solid.
The ACX plywood can be made of hardwood that is characterized by density or a mixture with some light hardwood. The layers inside of it are glued with a waterproof permanent phenolic glue which is quite strong and makes the plywood durable. This feature enables the ACX plywood to be suitable for exterior use, i.e., exposed to weather conditions.
ACX plywood can also be used for indoor constructions where weather changes can have their impact. So, if you want to build something for the inside of your house that will still be exposed to different weather changes, you can freely opt for ACX.
Marine Grade Plywood
Marine-grade plywood is known as the highest grade of plywood, which means it has the strongest features and properties among all types of plywood. Marine-grade plywood can be found in different grades, such as A-A, A-B, and B-B. The wood that is used for the production of this type of plywood is usually Douglas Fir or Western Larch wood.
The glue used in marine plywood is waterproof permanent phenolic glue or also known as WBP. This is the highest-quality glue, meaning that it is understandable why marine plywood is one of the best types of plywood for exterior construction. Therefore, if you want to build something quite big outside, your best option would probably be marine-grade wood.
The veneers in the marine-grade plywood are known to be better than the ones used in exterior-grade plywood. You will rarely find any defects in this kind of wood, but you might notice some sport, although they are not so common. However, the back and the front of this kind of plywood are smooth and strong; therefore, you can expect excellent durability if you decide to use it.
In addition, marine-grade plywood is characterized by extreme density and strength. You will see no holes in it, as may be noticed in exterior grade plywood. Also, the edges are sharper and cleaner than any other type of plywood. Marine-grade plywood might be more expensive than other types, but it will definitely last the longest of all.
If you consider the name of this plywood, you will understand that this type of wood is intended for building boats or similar marine constructions. This means that there are no holes in it, and this type of plywood is not as prone to crack as other types might be. So, you should expect great firmness, especially when building something bigger outside.
What Are The Main Differences Among Exterior Types Of Plywood?
The price and the construction are the main factors that make differences between the exterior plywood. For instance, marine-grade plywood is known to be the most expensive in the line of other types of plywood intended for exterior use. This is because marine-grade plywood is built in great strength and with high-quality materials, meaning it is the best choice if you are looking for exceptional durability.
CDX can also be used for some smaller exterior constructions, and it is the least expensive one. However, you should know that it is not considered the best choice since it includes low-grade materials. That means that this type of wood would not last long under weather changes and conditions, so you should not rely on it if you are planning to build something bigger.
That is why ACX is regarded as the better choice, i.e., the middle ground among the options. ACX is not as expensive as marine-grade plywood, but it is also not the cheapest one. Price is not always a determiner in quality; however, in this case, the amount of the price applies when it comes to estimating the quality.
Furthermore, the differences might arise when it comes to looks as well. For instance, marine-grade plywood is finely manufactured with a smooth surface that can withstand changes, such as painting.
Also, thickness is an important factor that makes a difference among the types of plywood. For instance, marine-grade plywood is characterized by great thickness, i.e., it is the heaviest, so it is the most solid type of plywood. That is why you can use it for the construction of boardwalks or shelves.
How Is Plywood Used For Exterior Construction?
You might be wondering what people build with plywood outside their houses. Actually, there are many things that you can design outside and be perfectly stable with the correct type of plywood.
The first thing you need to consider is the necessity of the plywood to be resistant to weather changes, such as rain, wind, snow, etc. Even if you are using the plywood inside, you have to think about humidity, so you have to think about the environmental factors at all times.
People use plywood to make different kinds of constructions, such as decks, walkways, benches, gazebos, and so on. These are the most common constructions in which plywood has proven to be very helpful and study. If you consider that these are all big constructions, you can imagine the strength of the exterior plywood.
However, plywood is generally not so good-looking as other types of wood that do not need a lot of alterations to get a good look. Nonetheless, plywood is adaptable and paintable, meaning you can make it look great if it is important to you. Therefore, you should not worry about the look since plywood allows changes as long as they are correctly done.
The blemishes and knots that can be found on the plywood are easily fixable if you use some good lacquers or paints that are suitable for a particular type of plywood. The front of the exterior plywood is usually smooth, meaning it gives you the chance to make the desired changes on the outside.
How Long Does Exterior Plywood Last Outside?
Generally, plywood can last around 20 years. However, the number of lasting years for plywood usually depends on how you treat your plywood constructions. It is of crucial importance that you maintain the plywood properly so it can achieve its lifespan.
Each type of plywood requires particular care, i.e., a special way in which it should be maintained. Firstly, it is essential to clean your constructions regularly since debris can be a real enemy of wood, especially plywood. Therefore, you need to consider cleaning from dust and other debris at least every three months.
In addition, you have to find out the proper way to keep your type of plywood in good condition. There are a lot of substances that can be applied to plywood to keep them shiny and clean, but also there are special cloths or other tools that will not cause any damages or scratches when you clean your constructions. Usually, the wisest thing you could do is contact your manufacturer and discover how you can keep your plywood in good condition so it can achieve its lifespan.
As you could see, there are types of plywood that are considered quite sturdy and durable for exterior use. There are some pricey types of plywood and the less expensive ones, so you need to think about whether it would be worth it to spend money on plywood that is quite expensive.
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