Types and characteristics of moisture-resistant plywood

Plywood that is resistant to moisture is a flexible building material that can withstand dampness and relative humidity. It’s a well-liked option for projects in bathrooms, kitchens, and outdoor spaces where standard plywood might not hold up.

This kind of plywood is available in a variety of shapes, each intended to fulfill a distinct purpose. There’s probably a type of moisture-resistant plywood that’s ideal for your project, whether you want to build a sturdy floor, strengthen a wall, or make furniture that won’t warp in wet environments.

Making an informed choice and ensuring that your work endures even in demanding environments can be achieved by being aware of the various types and their traits.

Production of waterproof plywood

The following procedures are part of the technology used in the manufacture of multilayer boards:

1. After cutting, deciduous and coniferous tree logs are delivered to the primary processing site. At this stage, the bark and branches are removed. The cleaned raw material is sawn into blanks.
2. The logs are placed in a bath, where they are kept until the required humidity is reached. Water is used as impregnation, various modifiers can be added.
3. The blanks are securely fixed on a peeling machine, unscrewed, and sharp cutters remove a thin layer of wood. Parts can be made using other methods, but this is the most commonly used.
4. The veneer is sent to the quality control section, where quality calibration is carried out and heavily damaged fragments are removed. Plates that do not have significant defects are used to create the outer layer.
5. The material is sent to the glue processing line. The moisture resistance parameters of the finished product depend on the composition used. The method of application is also important: mixtures can be laid only on top or impregnated with veneer.
6. A multilayer plate is assembled. The number of layers can vary from 3 to 21. There are two main pressing options: hot and cold. The first involves the effect of pressure and temperature, the second – only holding under the press for 6-8 hours.

Decorative finishing is done at the very end. Grinding and film cladding (to create a laminated panel) may be part of the process, depending on the material’s intended use and the necessary properties.

Note: An overview of the main features of every product must be included on the label. According to standard, the designations can be etched or indicated on a sticker.

Types of boards

The production method and technical specifications of the available options vary.

Pressed plywood

Chip-based OSB panels are referred to by this name. These goods are some of the most widely used building supplies.

There are some subtleties to the plywood’s manufacturing technology:

• Chips of different sizes are used for layers, which ensures strength and reliability.
• Due to high pressure, the pressed structure acquires the necessary stability.
• The chips are laid in layers in different directions.

A further processing step gives the material a moisture-resistant effect; however, this indicator is only present in products rated 3 and 4. Owing to its enhanced attributes, the final category finds application in demanding outdoor settings.

Glued version

This veneer-made product is reasonably well-liked. Different compositions are employed for layer connections.

Currently, there are the following types available:

1. FC. Based on urea glue with phenolic additives. It stands out for its good resistance to moisture, but without direct contact, therefore the boards are used exclusively for interior cladding. To enhance the properties, the parts can be processed at home with special primers and waterproofing mixtures.
2. FSF. The veneer to produce such moisture-resistant panels is glued together using phenol-formaldehyde resin. The structure of the products is preserved even in direct contact with liquid, so the material can be used for facade work.
3. FBK. Made by impregnation with bakelite varnish. The resulting products are characterized by increased strength and are suitable for use in difficult climatic conditions.
4. FBS. Also called "marine" or "Finnish" plywood. It is produced using a bakelite composition, but, unlike the previous version, alcohol-soluble glue is used. The material has excellent performance properties, includes varieties FBS-1, FBS-A and FBS-1A. The surface of the products is completely waterproof, so even direct contact with sea water is allowed.
5. FBV. The peculiarity of this material is that a water-soluble bakelite composition is used to glue the veneer. The panels are quite strong, but do not have a water-repellent effect, so they are not recommended for outdoor use and in areas with constant high humidity. Includes the FBV-1 variety.
6. FOB (FOF). This category includes decorative and laminated options. Due to the presence of cladding, the products cope well with harmful external influences.

Because the first variety is brown, and the second is black, it is easy to distinguish between the brands FBS and FBV.

Sheet sizes

The boards’ dimensions are established in compliance with the GOST standards. Producing goods in a different format is permitted, but only if the necessary guidelines are followed.

The most widely used sizes are as follows:

• FC sheets are most often produced with dimensions of 1515 x 1525 mm and a thickness of 3, 4, 8, 10, 12, 15 and 20 mm. Such products are small-format and are perfect for indoor work.
• FSF boards are in demand in different sizes: length – 2400 and 3000 mm, width – 1220 and 1500 mm, thickness – 9, 12, 15, 18, 21 and 24 mm. Large dimensions provide the ability to quickly finish the building from the outside.

• FBS products have parameters of 1525 x 1525 mm and thickness of 10, 12, 15, 18, 20, 21, 25, 27 and 30 mm. The material is quite durable and can withstand even serious mechanical impact.
• FBV has dimensions of 1220 x 2440 mm, thickness – 7, 10, 12, 15, 18 and 21 mm.

The only veneer used to make premium plywood that resists moisture is birch. The degree of grinding can have an impact on the moisture resistance parameters because complete processing removes the fine pile, which absorbs excess liquid the fastest.

Be aware of this! The longest panels are made of baked plywood and range in length from 5.7 to 7.7 meters. Its format is perfect for finishing with minimal seams.

Because it is strong and adaptable, moisture-resistant plywood is a great option for humid environments. Its durability guarantees that it is a good choice for outdoor projects, furniture construction, and other applications due to its resistance to warping and delamination.

You can choose the moisture-resistant plywood type that best meets your needs by being aware of the various varieties and their features. There is a type of plywood that meets your needs, regardless of whether you’re looking for strength, aesthetics, or a particular degree of moisture resistance.

Purchasing the proper type of moisture-resistant plywood not only extends the life of your projects but also gives you peace of mind because you know that your labor will endure difficult circumstances.

Plywood that is resistant to moisture is a multipurpose material that can tolerate high humidity levels, which makes it perfect for use in damp environments like bathrooms and kitchens. It is available in several varieties, each with unique qualities appropriate for a range of uses. Selecting the appropriate plywood for projects where water resistance and durability are essential requires an understanding of these types and their distinctive characteristics.

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