What is GVL and GKL: what is the difference, sheet sizes, types, which is better

Recently, “dry” construction and finishing technologies have become more and more popular. It is understandable. With less time spent, the result is very worthy. It’s just a matter of choosing the right materials. If you want to level the walls, ceiling, make a floor or sheathe a frame, but do not want to use potentially hazardous materials containing formaldehyde, you will have to choose from sheet materials made from gypsum. These are gypsum fiber (GVL) and drywall (GKL). But deciding which is better to use – GVL or GKL – is not so simple. Both materials have their pros and cons. And, the most reasonable thing is to use both, but in those areas where their properties will be in demand. 

GVL and GKL: what is it in construction

Drywall and gypsum fiber are relatively new building materials. They appeared a couple of decades ago, but have already confidently replaced traditional materials. In order to understand GVL or GKL, it is better for you to use it, you need to have a clear idea of ​​uXNUMXbuXNUMXbwhat kind of materials they are, what are their advantages and disadvantages. Based on this knowledge, you will be able to make the best decisions yourself. Because it is impossible to say unequivocally which is better – GVL or GKL. Somewhere one material is more suitable, somewhere it is better to use the second. So let’s figure out what these materials are and what types of GKL and GVL exist.

GKL: what is it and what are the types

GKL is an abbreviation for the name Gypsum Cardboard Sheet. This material consists of two cardboard sheets, between which there is a layer of gypsum. They are connected to each other with building glue. It is often called “drywall”, or the abbreviation GKL is used, sometimes you can hear “gypsum board”. The latter name is found zonal – more common in St. Petersburg and its environs. In this region, drywall was supplied by the Finnish company Gyproc (“Gyprock”), which gradually became a household name.

GKL is used for “dry” leveling of walls or sheathing of frames in frame housing construction. Suitable for indoor use, too fragile for outdoor use. Use drywall for walls, partitions, ceilings.

In the production of drywall, thick and smooth cardboard is used. It serves as a reinforcing and shaping element. Gypsum layer gives strength, keeps its shape. In most cases, a sheet of drywall has a thinner edge along the long side (there are even, with right angles). This allows you to carefully putty the joints when docking. So for some types of finishing materials it is not necessary to putty the entire area.

They produce drywall for different operating conditions, for easy recognition they use cardboard of different colors (gray, green, pink):

• For rooms with normal operating conditions – standard GKL. Has a gray color.
• For rooms with a high level of humidity – moisture resistant GKLV. Dyed green.
• For fire-hazardous premises / buildings – fire-resistant – GKLO. Has a pink color.
• In rooms with increased fire hazard and high humidity, GKLVO is used – refractory moisture-resistant drywall.
• Recently, soundproof drywall (GKLZ) has become popular. It has a high density gypsum core and is reinforced with fiberglass. Designed to increase the sound insulation of frame-sheathing structures of walls, ceilings and partitions. The leaf is purple or blue.

Now you know what GKL is, what types of drywall are and where they are used. It is a popular material for interior decoration. It does not contain harmful substances, although gypsum dust, which may appear during operation, may present some danger. To decide which is better GVL or GVK, now let’s talk about gypsum fiber.

GVL – what is it, what are they made of, what types are there

The name GVL is also an abbreviation of the technical name of the sheet building material: Gypsum Fiber Sheet. This material is made from a mixture of gypsum with cellulose fibers (waste paper is fluffed). The mass is mixed with water, sheets are formed from it under a press, which are brought to normal humidity (dried).

GVL is also used for dry leveling of walls and ceilings, sheathing frames, flooring. Unlike GKL, it has a “basic” incombustibility, since the cellulose is covered with a layer of non-combustible material – gypsum. GVL is produced with two types of edges – flat and folded. The seam edge is removed with a planer, the chamfer depth is about 2 mm, the width is about 30 mm. When mounted on walls, this allows you to further strengthen the seam (lay a reinforcing mesh) and putty it.

Gypsum fiber boards acquire special properties with the help of special additives. On this basis, there are the following types:

• Standard – GVL. For installation in rooms with normal humidity.
• Moisture resistant – GVLV. Used in rooms with a high level of humidity, to level the floor without screed.
• Moisture-resistant material of increased strength for flooring. GVLV EP is marked (moisture resistant GVL Floor Element).

Externally, moisture-resistant sheets are no different from standard ones. If the manufacturer is normal, the sheet is marked, in which, in addition to the size of the sheets, the type is affixed – GVL or GVLV. They also differ in the type of surface: GVL are polished and unpolished. Polished (“Knauf”) are much higher in price, but do not require mandatory puttying of the entire surface before finishing work.

GVL and GKL: properties and comparison

So far, there is not much difference between GVL and GKL. Both are sheet material that can be used for wall and ceiling cladding. Only gypsum fiber is suitable for flooring, and drywall is not. This is just the beginning. Let’s understand further.

Density, strength

If we compare GVL and GKL, then gypsum fiber has a higher density, and, accordingly, with the same thickness, greater strength and mass. Great strength – it seems to be good. In any case, GVL is not so easy to break through with a blow. Another plus is that you can safely hang shelves on a frame wall sheathed with GVL.

On the other hand, higher density makes installation more difficult. Not every self-tapping screw can be screwed into a gypsum board without pre-drilled holes. You can do without drilling, but only if you use self-tapping screws and a powerful screwdriver. Moreover, without preliminary countersinking (drilling a hole of a larger diameter), it will not work to “drown” the hat in gypsum fiber. When sheathing GVL in two layers without pre-drilling holes, it may turn out that the screw screwed into the second sheet “tries” to squeeze out the bottom one.

Drywall has less strength, it can be pierced by a fist. But ordinary self-tapping screws easily “enter” it. When installing the GKL, the most important thing is not to overtighten or tear the cardboard with the screw head. Otherwise, it falls into the plaster layer, which bursts. You have to turn somewhere else. If you “screw it up” several times in a row, you will have to change the sheet, since it simply will not hold.

And, by the way, on a wall sheathed in one sheet of GVL, a properly installed special dowel (butterfly or also called chamomile) can withstand a mass of 80 kg for a long time. The question is that it is necessary to comply with the technology.

GKL and GVL weight

Now about how high density is bad. The first disadvantage has already been described: it is more difficult to install fasteners. The second is high density – this is a large mass. That is, for the installation of GVL under the same conditions, a more powerful frame is required. When transporting, you will have to take into account the tonnage, it is more difficult to work with heavy sheets. The weight of one sheet of GVL is calculated in tens of kilograms. For example, Knauf gypsum fiber boards (“Knauf”) have the following parameters:

• a sheet with dimensions of 2500 * 1200 * 10 mm weighs about 36 kg;
• GVL 2500 * 1200 * 12,5 mm has a mass of 42 kg;
• the floor element 1550*550*20 mm has a mass of about 18 kg.

Plasterboard sheets are much lighter (see table).

If we talk about the mass of a square meter of a gypsum-fiber sheet, it can be calculated by the formula:

• The mass of the GVL square cannot be less than 1,08 * S,
• but cannot be more than 1,25*S.

Where S is the nominal sheet thickness in millimeters. So it’s easy enough to determine the range of values. However, for some reason, manufacturers do not indicate the weight of one sheet. This data can only be found at Knauf. According to their information, the picture looks something like this:

• GVL 10 mm thick – 12 kg / m²;
• GVL 12,5 mm thick – 14 kg / m²;
• EP 20 mm thick – 21,5 kg / m².

When compared with the average weight of gypsum boards, fiber gypsum boards will be somewhat heavier. And when carrying, you need to think about how not to break them. Naturally, it is necessary to fix the GVL on a more powerful base.

Flexibility and fragility

Drywall, due to the fact that the gypsum is between two layers of cardboard, is more flexible. Cardboard performs the task of reinforcement, taking a significant part of the load on itself. Especially under bending loads. For example, a GKL sheet can be lifted from one side by holding the short side. It will bend but not crack. If you try to carry out the same operation with a gypsum fiber sheet, it will crack.

Another plus of GKL is that they can finish curved surfaces. There are several technologies, thanks to which you can make arches, columns, smoothly curved reliefs on walls and ceilings. GVL does not provide such an opportunity. It very poorly perceives bending loads both along and across the sheet: the cellulose fibers are very short and the plate simply breaks. So if you need to finish curved surfaces, the choice between GVL or GKL is simply to make in favor of the second.

Sound insulation and thermal conductivity

When choosing a material for sheathing, indicators such as thermal conductivity and sound insulation are important. As you know, they depend on density, since GOSTs allow a fairly wide fork in the density of GVL, you need to look at these characteristics for each specific manufacturer. So that you can at least roughly navigate, there is such data:

• Thermal conductivity GVL with a density of 1000 kg/m3 to 1200 kg/m3 has a thermal conductivity of 0,22 W/m °C to 0,36 W/m °C.
• The thermal conductivity of GCR is approximately in the same range – from 0,21 to 0,34 W / (m × K).

If we talk about sound insulation, the same picture is observed: the characteristics are approximately equal. GVL gives only 2 dB better protection compared to GKL. It is also worth remembering that if desired, you can find acoustic drywall. It has special characteristics, it is used for lining shops, concert halls, studios. If we talk about private housing construction, it should be used in bedrooms.

If you look at the characteristics, there is no difference in sound insulation between GKL and GVL. But this parameter takes into account the “conduction” of the sound. There really isn’t much difference here. Here is how it feels to be. And significant. A room sheathed with gypsum fiber boards is much quieter. It’s not that noisy. Sounds from a smooth cardboard are reflected, and in the inhomogeneous surface of the fiber plates they “get stuck”. So if silence in the house is important to you, choosing between GVL and GKL, opt for gypsum fiber.

GVL or GKL: which is better?

Both have their admirers and detractors. You will have to decide which is better GVL or GKL on your own. In this section, we will try to compare them according to the most significant parameters. Let’s go over the sizes. Drywall is produced in a wider range both in terms of sheet sizes and thickness:

• GKL sheet thickness: 6,5 mm, 8 mm, 10 mm, 12,5 mm, 14 mm, 16 mm, 18 mm, 24 mm. The last three are very rare.
• The height of the GKL sheet can be from 2000 mm to 4000 mm in increments of 50 mm.
• GKL width – 600 mm or 1200 mm.

As you can see, the range is more than wide. Another thing is that there are usually two or three types on sale. But, with a strong desire, everything can be found / ordered. Although, it is usually easier (and cheaper) to buy what is available.

Less fortunate with the dimensions of the GVL. We have only two options for gypsum fiber boards: 2500*1200 mm (standard) and 1500*1000 mm (small format). Both options are available in 10mm and 12,5mm thicknesses. All. There are no other standard sizes. There is also GVL for the floor. Its dimensions are 1200*600 mm, thickness is 20 mm. May or may not be chamfered.

As a result, it is possible to say that GVL or GKL is better only specifically for the field of application and operating conditions. In a nutshell, here’s how the areas of application can be divided:

• GVL for walls and ceilings is better if fire resistance is required or if it is necessary to increase the rigidity of the structure (in skeletons).
• It is better to put GVL on the floor, since it reacts less to humidity, does not change its properties.
• GCR is indispensable if you need smooth lines or complex multi-tiered structures. A multi-level ceiling, arches, columns, rounded walls and corners are just drywall.
• If you need to achieve good sound insulation of the second floor, it is better to hem the ceiling with GVL.

As you understand, there is no way to finally say which is better than GVL or GKL. In some conditions, one material is better for one task, the characteristics of another are more suitable for another.