Features and application of gypsum boards

GSP slabs are a relatively new and unfamiliar material to a wide audience. Gypsum board can be used for walls and floors, you just need to know the characteristics of moisture-resistant sheets and the rules for their use, how to choose the right option. It is no less important, however, to figure out how to cut the wood-gypsum sheet and mount it.

GSP, or more fully - gypsum chipboard, is a relatively recent material. Only a few firms are engaged in the production of such a product in Russia. A significant part of the production is brought from abroad, therefore it is quite expensive. The share of gypsum accounts for up to 83%, shavings - a maximum of 15%, the remaining mass - water and special improving additives; due to cellulose fibers, the sheet becomes stronger.

The original wood raw material is cleaned and crushed. Moistening is produced, due to which the connection is as reliable as possible. Gypsum, modifying substances and a certain amount of liquid are added to the shavings. The resulting mass, as soon as it reaches the required consistency, is placed under a press. There it is formed properly.

Wood-gypsum board is quite durable. Its density reaches 1250 kg per 1 m3. Such a product will carry significant loads in the longitudinal and transverse planes. Importantly, it has high bending resistance. Standard stability varies from 8 to 16 MPa. The exact value of the parameter is determined by the thickness of a particular element.

GSP is extremely environmentally friendly. No toxic substances are used in its manufacture. However, it should be borne in mind that when working with the material, a suspension may form. Therefore, fitters must use respirators. In favor of gypsum boards, their fire safety also testifies.

The spread of fire is effectively contained precisely by the presence of plaster. Even if the structure is exposed to excessively strong heating, toxic substances will not be released. In addition, the gypsum board is moisture resistant - typical options absorb up to 30% of the liquid in 120 minutes of "bathing". Specialized components can reduce this indicator by another 3 times. GSP perfectly suppresses extraneous sounds (the sound insulation index is 32-35 dB), in addition, this material will help to increase the energy efficiency of the building.

All GSP sheets are divided into two types: regular type and GGPV. The second type has increased resistance to moisture. The gypsum board is used for both primary and final layouts. It is customary to divide it into:

• panels for painting;

• vinyl;

• coated with polyvinyl chloride;

• having a polymer lining of the variety.

It should also be borne in mind that a moisture-resistant board can be used much more often than the usual type. However, it will cost much more. As a result, it is actually used mainly in damp rooms, where there is a direct need. In general, such options are known as:

• wall;

• partitions;

• flooring.

Wall covering usually requires a higher degree of evenness. Achieving the same effect with plastering is very difficult and time-consuming. In addition, particle sheets reliably contain background noise and heat loss. Partitions made of GSP are distinguished by excellent density and rigidity, which makes them more reliable and stronger. There will be no special requirements for installation.

On top of that, GSP can be used for:

• finishing of ceilings;
• rough alignment of walls in new buildings;
• laying the sub-floor.

The dominant type of GSP is a rectangular structure with a thickness of 0.8 to 2.8 cm. It always has relatively smooth surfaces from the “face” and from the inside. They are characterized by straight ends. Grinding of the ends is almost never carried out. Other types of GSP are just modifications of the main type:

• polished (more often they grind the front side, less often the back side);

• having milled folds (sections selected at the ends with a depth of 10 to 30 mm);

• waterproof (with surface treatment with hydrophobic compounds).

Like any wood product, gypsum board necessarily has standard sizes. By default, the dimensions are:

• 50, 150, 250, 300 cm in length;

• 125 cm wide;

• 8, 10, 16, 20, 24, 28, 12 mm in thickness.

The mass of the sheet for a number of standard sizes is as follows:

• 50x125x0.8 cm - 6 kg;

• 50x125x1 cm - 8 kg;

• 50x125x1.2 cm - 9 kg;

• 150x125x0.8 cm - 18.75 kg;

• 150x125x1.2 cm - 24.44 kg;

• 300x125x1.2 cm - 56.25 kg.

The key physical properties are:

• density - from 1100 to 1200 kg per 1 m3;

• humidity - from 2 to 3%;

• noise isolation - 30-35 dB;

• fire safety level - G1, B1, D1 - KM1, RP1.

Buying a gypsum board is an extremely responsible business. Counterfeit or substandard products have very mediocre characteristics. However, the price of the product is not always cheap. High-quality specimens are marked with an indication of all dimensions, the level of resistance to moisture, the type of surfaces and edges. Information about the legal address, company name and place of official production should also be provided.

All this should be completely in Russian and stated clearly even for non-professionals. In the absence of even a small part of the necessary data, there is a counterfeit or low-quality product. A conscientious seller is also obliged to present certificates of conformity, sanitary-hygienic and fire safety on demand. Formally, certification is optional, but any conscientious manufacturer must pass it. It is also required to carefully inspect the goods in order to exclude the impact of illiterate transportation and storage.

The most important thing is to take into account that the gypsum board is significantly heavier than ordinary drywall. The double weight makes installation possible only by two people. If you have to work with slabs over 2.5 m long, it is advisable to completely connect a third person. Do not think that you can do with the same frame as for a drywall sheet. You will definitely have to use a damper tape.

It is used on all adjacent planes. We are talking about the joints:

• profile and floor;

• wall profile;

• profile and GSP.

If this rule is violated, you cannot count on at least some kind of sound insulation. Another important point is the width of the product. If for gypsum board it is 120 cm, then for gypsum board it is 125 cm. The typical width of insulation or sound insulation is 60 cm. Sometimes an indicator of 62.5 cm is found, but this significantly reduces the choice.

Since the plasterboard block is heavy, and a number of heavy things can be attached to it, it is necessary to use as strong a frame as possible. Rack profiles from the edges of the sheets are screwed "backs" to each other. This creates a double profile. A vertical guide is placed in the center of the slab, inside which a 5x4 cm bar is placed.

Horizontal jumpers are formed from a profile with a step of 60 cm. Sometimes the step is increased to 120 cm, but in this case a checkerboard arrangement is used. The profile and the timber together occupy 4 cm. As a result, the insulation will calmly lie in the provided cells. On such a profile frame, people weighing up to 130 kg can safely go up and down.

In some cases, they are limited to simply twisting the double profile on the backs. Attention: wherever the slab adjoins the floor, wall or ceiling, you will have to leave a gap of at least 1 cm. The spacing of the screws is usually 20 cm. With particularly high requirements, the gap can be reduced to 15-18 cm. The points of contact with the wall or corners during the filling of the seams will have to be reinforced with a mesh (in pure form or with the addition of plastic corners).

The quality of the profile cutter plays an important role during installation. A worthy tool pays off quickly. At the same time, a low-quality device will often fail, and it will take a lot more time. If a profile with a bar is used, you will need to fasten the cross members using screws. If a double profile is taken, you can limit yourself to work with the use of a cutter.

Many amateur craftsmen try to use the Knauf profile to obtain the frame. This is a fairly durable and high quality option. Driving ordinary screws into the plate without pre-countersinking is impossible. The only exception is the fastening through the seam edge. There is a solution - you only need to purchase high-quality pointed screws 3.2 cm long.

A separate topic is how to cut plasterboard products. The habitual “cut with a knife and break with neat punches” approach for drywall users will not work here. GSP is comparable in strength to plywood. 1-2 sheets can be cut with a hand hacksaw. If you have to cook more material, you will need an electric jigsaw.

It is worth considering that contrary to popular belief, it is not the leaf itself that is "dusty", but the crushed substance. Experienced builders work in a respirator. Another good way is to use a vacuum cleaner. The use of large-toothed saws also helps to reduce dust emissions. When it is planned to finish the whole room with a chipboard, theoretically you can limit yourself to puttingtying only the joints.

In this version, there will definitely not be a uniform color. And therefore it is guaranteed that you will have to putty everything. Given the smoothness of the front side, it must be pre-primed. The procedure for applying the putty itself does not differ from the similar work with gypsum board. When planning to stick wallpaper, you need to check if the screws have left characteristic rusty spots; you can eliminate them by applying paint.

For an electric jigsaw, it is recommended to buy blades made of durable alloys that keep sharpening for a long time. For serious permanent work, it is recommended to buy professional or semi-professional equipment that can cut at high speeds. Strong pressure on the jigsaw is contraindicated, it is recommended to drive the tool not in one line. A circular saw helps to cut the sheets as evenly as possible.

The fastening of the GSP itself is usually done using self-tapping screws. Fasteners made of acid-resistant stainless steel or galvanized steel are best suited. These requirements are especially important for wet rooms. It is not recommended to nail the gypsum board with nails, but they are needed to form the fastening frames and wooden battens. The best choice is a weaving nail with notches.

On the floor, the slab is mainly placed on logs. This option allows you to use even an initially uneven base. As a lag, a 5x8 or 5x10 cm bar is used. Waterproofing materials, such as glassine or roofing material, are laid under it.The perimeter of the room at floor level is covered with soundproof tape (preferably foamy).

The following video provides an overview of gypsum boards.