Views: 208 Author: Site Editor Publish Time: 2024-11-29 Origin: Site
Concrete forming plywood, a specialized material engineered for concrete construction, is essential for achieving the desired shape and finish of concrete structures. Its durability, strength, and resistance to water and weather make it a reliable choice for various construction projects. This comprehensive guide explores the different types of concrete forming plywood, their applications, and factors to consider when selecting the right material for your project.
What is forming plywood?
Forming plywood (plywood formwork, concrete forming plywood) is a specialized material designed for concrete construction. It is engineered to withstand the harsh conditions of the concrete pouring process, including multiple reuses, exposure to water and extreme temperatures, and contact with alkaline substances. Its surface is resistant to mold, fire, and is easy to clean, making it a durable and practical choice for construction projects.
Advantages of concrete forming plywood：
Unlike regular plywood, it has several distinct features:
Durability and strength
Concrete forming plywood is designed to be exceptionally durable and strong. It can withstand the immense pressure exerted by wet concrete without warping or bending. This strength is crucial for ensuring that the concrete structure retains its desired shape and dimensions.
High-quality surface finish
One of the key characteristics of concrete forming plywood is its smooth and high-quality surface finish. This smooth surface is important because it directly affects the finish of the concrete once it sets. A smooth formwork surface results in a smooth concrete surface, which is often essential for both aesthetic and structural reasons.
Water and weather resistance
Concrete forming plywood is treated to be water and weather-resistant. Given that it is often exposed to moisture from wet concrete and outdoor conditions, this resistance ensures the plywood doesn’t degrade or delaminate over time.
What plywood is used for forming?
The type of plywood used for concrete forming, commonly referred to as formwork plywood, is specially designed to withstand the pressures and conditions associated with concrete pouring and setting. Here are the main types of plywood used for forming:
1. HDO (High-Density Overlay)
Description: HDO plywood has a resin-impregnated surface that provides superior durability and a smooth finish. It is highly resistant to water and wear.
Usage: It is used in applications where the concrete surface finish is crucial, such as in architectural concrete and exposed surfaces.
2. MDO (Medium-Density Overlay)
Description: MDO plywood is similar to HDO but has a medium-density overlay. It is also durable and provides a good surface finish but is generally more cost-effective.
Usage: Suitable for a wide range of construction projects, offering a balance between quality and cost.
3. FFP (Film-Faced Plywood)
Description: Film-faced plywood is coated with a waterproof film on both sides, enhancing its durability and making it suitable for repeated use.
Usage: Commonly used in large-scale construction projects due to its reusability and excellent surface finish.
4. BBOES (B-grade, B-grade, Overlay, Exposure 1, Struct 1)
Description: BBOES plywood features a high-quality finish with a smooth overlay, making it suitable for producing a good surface finish on concrete.
Usage: This type is ideal for projects where a fine concrete surface is required.
5. BB Plyform
Description: BB Plyform is a type of plywood specifically manufactured for concrete formwork. It is made with high-quality veneers and a durable resin-impregnated surface.
Usage: It provides a smooth finish and is used in applications where the appearance of the concrete surface is important.
6. Marine Plywood
Description: While not specifically designed for concrete forming, marine plywood is sometimes used due to its high resistance to moisture and strong structural properties.
Usage: Suitable for formwork in environments where high moisture levels are expected.
What are the sizes of form ply?
Sheet dimensions
4 feet x 8 feet (1.22 meters x 2.44 meters) is the most common size and is widely used in the construction industry for a variety of applications. Besides, other sizes such as 4×10 feet (1.22 meters x 3.05 meters) and 4×12 feet (1.22 meters x 3.66 meters) are also available for specific needs.
Thickness
Here are plywood thickness for concrete forms:
1/2 inch (12 mm)
5/8 inch (15 mm)
3/4 inch (18 mm)
1 inch (25 mm)
The thickness of the plywood selected often depends on the specific requirements of the project, including the pressure of the concrete and the size of the forms being created. The thicker the plywood, the greater its load-bearing capacity. Thicker sheets are generally used for larger structures or when higher strength is required to support the weight and pressure of the concrete. Thicker plywood also tends to provide a smoother finish for the concrete surface, which can be critical for architectural projects where aesthetics are important.
Tips for purchasing concrete forming plywood
What are the best boards for concrete forms? To ensure optimal performance, select straight, flat lumber with minimal knots. This type of wood will provide the best support for the concrete as it cures. Besides, you also need to consider the following factors:
Quality and specifications: Ensure the plywood meets the required specifications for your project. Look for terms like HDO, MDO, or film-faced.
Reusability: Consider the reusability of the plywood if you plan to use it for multiple projects.
Cost vs. value: Forming plywood price varies depending on quality. Balance the cost with the quality and durability required for your specific project needs.
Local regulations: Check if there are any local building codes or regulations regarding the type of plywood used for formwork.
