Plywood For Formwork: Moisture-resistant Formwork 18 Mm And Construction Plastic Of A Different Thickness. What Other Types Are Used? Their Sizes

2024 Author: Beatrice Philips | [email protected]. Last modified: 2023-12-16 05:33

Construction based on a monolithic system is in demand in various spheres of life. This technology is based on the casting of structures using special forms and frameworks - formwork. For the manufacture of formwork, builders use various types of materials, but plywood has taken the leading position for many years. Despite the seeming simplicity of the design, special attention must be paid to the choice of material for the formwork, the quality of which will subsequently determine the reliability and durability of the product, as well as the accuracy of the concrete product. In this article, we'll take a look at everything about formwork plywood.

Peculiarities

Plywood for formwork is an irreplaceable building material that is used for the manufacture of formwork structures for both civil and industrial construction. For the device of the formwork of a concrete foundation, floor slabs, as well as for pouring walls, they are made from different types of plywood. Professional builders recommend paying attention to the following undeniable advantages of formwork plywood structures:

• high level of resistance to deformation;
• reliability;
• durability;
• multiple use;
• ease of installation and assembly of the structure;
• obtaining a flat concrete surface without connecting sections;
• no need for preliminary alignment;
• the possibility of making design changes directly during the installation process.

The versatility of plywood formwork also lies in its recyclability. If, after completing all construction work, the structure is no longer useful, then it can be sold or used as a material for the manufacture of floor panels or the lower layer of the floor covering.

We should not forget about the shortcomings of the material, namely:

• the need to install props every 50-100 cm;
• the need for mandatory cleaning and drying of the structure after work;
• obligatory storage in a dry and ventilated room.

Varieties

Despite the wide range of construction plywood, not all of its types are used for the manufacture of formwork. Experts recommend choosing only materials with improved technical characteristics of a rectangular shape, but it is better to refuse a round one. One of the most important criteria when choosing plywood is the type of adhesive used by the manufacturer to join the wood sheets.

Moisture resistant

Plywood, the layers of which are glued with an adhesive based on phenolic and formaldehyde resins, is moisture resistant and has a high level of resistance to moisture and temperature fluctuations. Due to these technical characteristics, structures made of this material can be reused even in unfavorable climatic conditions . Disadvantages - high level of toxicity and inability to use indoors. To increase the level of resistance to mechanical damage and prevent the appearance of chips and cracks, manufacturers use grinding technology, which not only improves the aesthetic appearance of the product, but also makes its surface as smooth as possible.

Plastic

Particular attention should be paid to a new type of formwork plywood - plastic. This building material is made of polymer plastic, which has a unique composition, design and technical characteristics. The main distinguishing features are the presence of two perfectly smooth sides and a corrugated middle. These features give the product the maximum level of strength, lightness and reliability.

The advantages are as follows:

• environmental Safety;
• wide temperature range;
• ease of care and storage;
• affordable price;
• color fastness;
• high level of resistance to fire, moisture and aggressive substances.

The following disadvantages should be noted:

• narrow scope;
• small size assortment.

Important! Some manufacturers produce plywood, which is only covered with plastic, and is based on ordinary wood veneer. This combination of materials allows to improve the strength of the material, as well as to increase its turnover by several tens of times.

Laminated

Laminated plywood board is an improved version of moisture resistant material, which is most often used for the manufacture of formwork. Most often, manufacturers use sheets made from deciduous trees for lamination. A distinctive feature is the presence of a smooth or corrugated surface with an anti-slip effect.

Bakelized

Bakelized plywood, which uses bakelite resin, has a high level of strength and resistance to mechanical damage. This composition is obtained by combining phenol with formaldehyde, which makes it possible to use the material in the most unfavorable climatic conditions and in conditions of sharp temperature fluctuations.

How to choose?

The choice of material for formwork is an important preparatory stage in the construction process, on which the quality of further work depends. In specialized construction shops you can see a wide range of plywood for formwork from both domestic and foreign manufacturers. Experts recommend paying attention to the products of local factories, which have not only high quality, but also an affordable price range.

When choosing this material, professional masters recommend paying attention to the following parameters:

• thickness;
• the size;
• grade;
• turnover;
• type of foundation.

Despite the wide range of thickness produced, which ranges from 0.3 cm to 4 cm, experts recommend paying attention to products with a thickness of 18 mm to 21 mm. It is these indicators that are most optimal for the manufacture of formwork for both civil construction and industrial, since they are able to withstand the pressure of concrete, and also have a small mass, which greatly simplifies the process of transportation and assembly of the structure. Products of this thickness also have an affordable price range, which significantly reduces the estimated costs.

When calculating the amount of materials, one should not forget about the size range of plywood sheets. Considering this indicator, you can avoid the appearance of unnecessary waste and scraps. The most common standard sizes are 1220x1220 mm, 1220x2440 mm, 1270x1525 mm . This size range is far from complete and consists of a huge number of other sizes. For large structures, builders recommend purchasing sheets of an enlarged format, which will help to avoid joints. For formwork of non-standard size, special sheets of the required format can be ordered.

We should not forget about the type of material that affects its strength and price range. Manufacturers produce extra-grade plywood and four other grades. For formwork, materials of the first and second grade with a high level of strength and a low price are best suited.

When choosing plywood material, you should pay attention to the type of foundation, on which the design formula depends. The calculated values for a striped concrete base are as follows:

• double the size of the perimeter of the structure;
• building height with allowances;
• the thickness of the material used.

Important! By this principle, you can calculate the amount of material for any manufactured structure.

The turnover indicator is the level of practicality of the material, as well as the possible number of its uses. The turnover rate depends on the following indicators:

• manufacturer;
• the quality of the raw materials used;
• technical operating conditions.

To increase the operating cycles, experts recommend covering the structures with a special grease (black), which better separates the sheets from the concrete and prevents the appearance of chips, cracks and breaks.

Construction is not only a necessary and exciting event, but also a process that requires knowledge, skills and practical skills. During construction, special attention must be paid to creating a foundation, which will subsequently become the support of the entire structure. The quality of this structure directly depends on the formwork used, which must be reliable, moisture resistant, and most importantly, not have joints. As a base material, builders use various accessories, but experts recommend making formwork from plywood, which has a large number of advantages over the background of ordinary wood.