GVL is considered to be one of the most popular modern materials for interior decoration. This abbreviation stands for gypsum fiber sheet, which is a dense finishing material made of gypsum and cellulose. It is a durable material commonly used for wall cladding and floor screed..
The main feature and advantage of gypsum fiber is strength and ductility. The homogeneous composition of the GVL board even allows you to hammer nails into it, like into a tree. A special microclimate is maintained in the room, decorated with gypsum fiber board, since the material is able to absorb excess moisture or give it away. Thus, gypsum fiber is a natural moisture regulator..
Gypsum board can be processed in different ways. For example, the mark “Ш” on the package means that the sheets are sanded, and “NSh” is an unpolished surface. When choosing GVL not for a rough finish, but for painting or for wallpaper, sheets with a polished surface are most often chosen, but if you need to glue some additional finishing material (panels or tiles) on top of GVL, then a plate with an unpolished surface is best suited.
If it is necessary that the joints of the GVL sheets are completely invisible during finishing, then you need to choose packages marked “FK” – sheets with special chamfers for an inconspicuous joint. If ordinary sheets are used, then the joints must be putty using a special reinforcing tape.
Gypsum fiber does not work well with silicate dyes and paints based on water glass. Any other paints can be used – alkyd, dispersed, and so on..
Most manufacturers are interested in the high quality of the manufactured building material, therefore, when purchasing GVL, you can safely demand GOST certificates of conformity and other documents confirming the quality of the products. If there are no documents, then it is better to refuse the purchase – the material may be of poor quality.
Advantages and disadvantages
Gypsum fiber boards have many advantages over drywall and other finishing materials..
Let’s consider the advantages of this material in more detail:
- the material has excellent heat-insulating and noise-insulating qualities, therefore, it is suitable for using the interior decoration of country houses and installing interior partitions in them;
- high rates of fire resistance, which is confirmed by special certificates;
- plates are hygroscopic, that is, they are able to absorb moisture from the air, and, if necessary, give it away;
- the moisture resistance of gypsum fiber boards is better than that of drywall or fiberboard;
- high-strength slabs, very dense, but also flexible at the same time;
- no deformation of the material due to changes in temperature conditions does not threaten you;
- it is an environmentally friendly material containing gypsum and cellulose;
- easily mounted on both a wooden frame and a metal one;
- the joints of the plates are easily masked;
- even a home craftsman can use slabs in construction and decoration;
- no significant waste, dust or dirt.
The GVL-canvas also has disadvantages, but there are very few of them:
- the plates are quite heavy;
- GVL is more expensive than drywall;
- if you do not follow the rules for installing GVL, then during further operation the material may crack or break;
- no special tools are needed for mounting or cutting GVL boards.
What is the difference from GCR?
GVL-plates are similar to drywall and glass-magnesium finishing materials, but they have their own characteristics.
- Gypsum plasterboard is a “sandwich” of two layers of cardboard and a gypsum layer, and GVL sheets are solid, since cellulose fibers are added to the gypsum mixture, pressed and dried. That is why GVL is stronger than drywall.
- Glass-magnesium finishing materials (MSL) differ from GVL in greater fire resistance, but are inferior in “naturalness”, since they contain, in addition to binders, magnesium oxide and magnesium chloride, and the fibers present in the composition of GVL are a waste paper processing product.
- GVL is a durable material, therefore, unlike GCR, it will resist accidental damage well. Anyone who has dealt with drywall knows that even an accidental light blow can damage this material. With GVL-sheets, you can rest assured that neither an accidental cork from champagne, nor an unsuccessfully thrown children’s toy will cause serious harm to the wall. Since the differences between GVL and GCR are associated precisely with strength, then it is important to note that gypsum fiber boards can be used when leveling the floor, and drywall will not work for this. When choosing a sheet of drywall, one has to take into account the dimensions of the room and the height of the ceilings, since a wall trimmed with one sheet is much stronger than one trimmed with several. A gypsum fiber wall can consist of several elements, this will not violate its strength.
- Drywall often crumbles when sawing, and with gypsum fiber, you can not be afraid of this – there will be no crumbling or chips during cutting. The gypsum fiber can be cut as required. It is necessary to say only about a large amount of dust when cutting, so all work is best done with glasses..
- Even if the gypsum plasterboard is wet, then it will not lose its properties – for some time it will simply become more plastic, and after drying it will return to its standard strength. By the way, if you are going to paste over the surface with wallpaper, then remember that the gypsum board can absorb glue.
- The difference between these two materials allows them to be used for structures with different purposes..
- Gypsum boards are much more difficult to bend., than drywall, so interior decoration with bends and oblique lines is best done with drywall.
- Gypsum fiber differs from drywall in greater resistance to temperature extremes, in particular, to freezing.
- For the installation of gypsum plasterboards and gypsum plasterboards, a frame is needed. Both those and other building materials require preliminary production of a supporting structure made of metal or wood. For GVL-plates, the frame structure must be stronger, and the profile must be at least 0.5 mm thick, since the plates themselves are quite heavy.
Due to the large weight of gypsum fiber boards, it can be difficult for one master to work with them. If you have to rely only on yourself, choose small-format options for GVL sheets.
The composition of the material (recycled waste paper and gypsum) gives a white-gray color to all sheets of gypsum fiber board. The gypsum to cellulose fiber ratio for gypsum fiber boards is about 80% to 20%. The density of gypsum fiber panels is about half that of red brick.
The tensile strength of GVL-sheet is very high: at a bend, the indicator will be 53 kg / cm2, and in compression – 100 kg / cm2. The thermal conductivity of the material reaches 0.36 W / mK and is similar to the thermal conductivity of expanded clay concrete. Warm to the touch.
Sound insulation of gypsum fiber board is at a good level – sound absorption reaches 40 dB and depends on the thickness of the material.
There are waterproof GVL and conventional. The swelling of GVL in water will be 1.5% in a day.
GVL-plates come in different sizes, but most often on sale we find sheets in the form of rectangles from 2 to 3 meters long and from 60 centimeters to 1.5 meters wide. The sheet thickness can be 10, 12, 14, 16 or 19 mm. In the interior decoration of premises, the material of the following parameters is usually used: 10 or 12 mm thick, 2500 mm by 1200 mm. The larger and thicker the GVL-plate, the more it weighs.
The first place in the Russian construction market is occupied by Knauf GVL-plates, therefore, we will be guided by them when determining the standard ratio of the size and weight of one panel..
The ratio of size and weight for conventional sheets of gypsum fiber board:
- plate 250x120x1 cm – 36 kg;
- plate 250x120x1.25 cm – 45 kg.
The ratio of the size and weight of GVL sheets for dry floor screed:
- plate 120x 120×1 cm – 17.5 kg;
- plate 120x120x2 cm – 17.5 kg.
GVL-plates are fire-resistant material, incapable of self-ignition. The flame does not spread over the surface of the material. On the packaging of the material and in the certification documents, the fire resistance category G-1 (hardly combustible) is indicated.
Moisture and deformation resistance is ensured by special processing.
In order to increase moisture resistance and resistance to deformation, gypsum fiber is impregnated with special latex compounds right during its production. This hydrophobic treatment will not only increase water resistance, but also provide optimal adhesion to other finishing materials and painting..
Gypsum fiber materials differ from each other depending on two criteria: size and purpose..
By appointment are allocated:
- Standard GVL boards used for construction and finishing work in rooms with standard humidity indicators. Durable materials, safe for human health, are widely used for the installation of internal partitions and other repair work.
- Moisture resistant GVLV plates. They can withstand high humidity for a long time, so they are used in the decoration of kitchens, bathrooms, even saunas and baths. Moisture resistance is acquired by processing the material with special water-repellent compounds.
- Slabs GVL- “superpol”. Produced by Knauf. Very strong and durable slabs, ideal for dry floor screed work. Superpol slabs are two welded sheets of gypsum fiber board, while they are slightly offset relative to each other to facilitate installation and obtain a reliable high-quality surface with excellent tensile strength. The dimensions of GVL sheets are determined by the requirements of GOST, while, as already mentioned above, some features of the material will depend on the size:
- Standard slabs 1200 × 1500 mm are used for finishing or building any surfaces. It is with them that the walls are aligned.
- Small format plates. Dense and heavy slabs are usually used for flooring. Usually they have a seam system (“in the lock”) when connected to each other.
Scope of application
The scope of application of GVL is very wide and is becoming wider. Over the past two decades in our country, the volume of “dry construction” has sharply increased, that is, without the use of mixtures, so the demand for gypsum fiber is growing steadily. So, GVL materials are used:
- in construction and repair work of residential and public premises;
- for wall decoration in industrial enterprises, as well as in trading floors and hangars;
- when cladding any frame structures and building walls;
- for installing partitions indoors;
- for finishing work when the walls need to be leveled;
- when installing floor coverings;
- as a decoration for wooden and other walls in country houses;
- in sanitary facilities (in the bathroom, shower or toilet) for subsequent tiling;
- when facing technical premises – storerooms, attics, etc .;
- when finishing basements with standard and high humidity;
- in the decoration of the balcony and loggia – as an independent or rough finish;
- for finishing premises with special fire safety requirements, for example, elevator shafts and evacuation corridors;
- due to its environmental friendliness, it can be used in the decoration of the premises of schools and kindergartens (the natural background radiation is three times less than that of the widely used brick);
- for installation of floor coverings in sports and dance halls;
- when installing underfloor heating, since GVL-sheets have good heat capacity;
- in rooms where a hanging cabinet, shelves or heavy doors need to be placed on the walls – gypsum fiber can easily withstand even very serious loads;
- when creating cabinets and boxes for hiding plumbing and other communications;
- gypsum fiber impregnated with antifungal agents is used in construction and repair work in medical institutions and swimming pools.
In general, we can say with confidence that gypsum fiber materials allow you to perform high-quality construction or finishing work in almost any room, while the owner of the room can count on their durability and strength..
What to cut?
When doing construction or finishing work with your own hands, it is often necessary to cut GVL-plates. Professionals note that, in general, this work is similar to cutting drywall, but you still need to remember some of the features. So, gypsum fiber bends much worse than drywall. Therefore, if you unsuccessfully position the sheet in front of the cut (for example, if the edge of the blade will sag strongly down from the cut), it may crack or break..
The tools that can and should be used when cutting drywall materials include construction knife with replaceable blades (the blades must be at least 12 mm thick) or a special hacksaw that allows you to cut GVL with almost no dust (you can also use an ordinary sharp hacksaw, but in this case, dust will be required).
Can be used grinder or circular saw, True, this method, although it is considered the fastest, is the most dusty and noisy. Of course, if the room is easy to ventilate, then it makes sense to use these tools, be sure to protect the respiratory tract with a respirator and special glasses – vision.
Professionals often use a jigsaw with a built-in vacuum cleaner, but the spread of dust still cannot be avoided – the vacuum cleaner does not have time to absorb its entire volume. Use a standard wood saw with a pitch of at least 4 mm for the jigsaw and do not forget to wear protective goggles and a respirator.
When working with any tool, safety precautions should be observed, and it is recommended to prepare GVL material. So, it is recommended to soften the sheet before you start sawing it. So the dust will be less, and it will be much easier to cut it. Use a rule or ruler to mark the scout line.
It is necessary to carry out along the marking line several times with a construction knife (it is necessary to carry out it more than once, but until a deep groove is indicated on the sheet – at least 2/3 of the sheet thickness). We put a special rail under the cut line and sharply cut the material. We fold the sheet up, not down!
Such a difficult matter as cutting gypsum fiber sheets is compensated by the formation of a smooth and even edge of the cut gypsum fiber boards, which do not need additional processing..
If, nevertheless, you did not succeed very smoothly, then the fit can be done using a conventional roughing planer, and a cutter knife or chisel will help prepare the fold.
Subtleties of installation
The installation of GVL-plates for walls and floors has its own subtleties. Nevertheless, these works can be done by hand..
Installation of GVL-plates to the walls in stages:
- prepare sheets of GVL (sawing, marking);
- prepare the surface (cleaning, leveling);
- mark up the profiles;
- stick a special sealing tape on the profile;
- attach the profiles to the walls using self-tapping screws; use dowels if necessary;
- fix gypsum-fiber sheets on the profiles using special screws, use only screws for gypsum fiber board !;
- the screw head is “recessed” into the sheet by about 1 mm, while it is important to ensure that the screws enter the material at right angles, and the fixing step should not be less than 25 cm;
- we work out the joints and screws with putty, after which we prime.
Gypsum panels can be fixed to walls and with mounting glue. In this case, the frame is not needed, and the technology for carrying out the work is as follows:
- prepare sheets of GVL (cutting, marking);
- prepare the base wall (cleaning and leveling the surface);
- carefully read the instructions for applying construction glue, since there are types of glue that are applied around the perimeter and stripes in the center (mesh) using a notched trowel, and there are types that are applied pointwise;
- apply construction glue to the GVL sheets;
- press the panels against the walls;
- seal the joints with putty and prime.
Installation of GVL on the floor is used before laying laminate and other finishing materials. Gypsum fiber helps to level the floor, strengthen it, make it moisture resistant and fireproof.
The technology for installing GVL-plates on the floor is as follows:
- If necessary, dismantle the old floor covering, including old logs.
- Remove construction debris and dust.
- Repair gaps in old floors. For this, you can use alabaster, assembly mixture or quick-setting cement..
- Mark the backfill level using a water level. It is advisable that the difference in the marks you put was no more than 6 cm.Be prepared for the fact that there will still be a difference, since the unevenness of the floors is a common thing.
- Install the waterproofing material. The first layer is dense polyethylene, glassine or roofing felt (the material must be chosen depending on the purpose of the room and remember that this layer serves as a vapor barrier). Lay polyethylene or other material with an overlap, and glue the edges with mounting tape. Waterproofing is laid so that its edges go onto the walls (we make a kind of bowl) above the waterproofing level marks. The edges of the film must also be glued to the wall. The second layer is insulation / waterproofing. Many craftsmen give preferences to expanded clay, as it has good performance characteristics. A wooden or reinforced concrete base is laid with a layer of waterproofing material.
- Flatten the expanded clay. For these works, use beacons from a guide metal profile and a level, paying special attention to the corners of the room and the space near the walls..
- If your room needs additional sound insulation, then use expanded polystyrene sheets for this, laying them between expanded clay and GVL boards.
- Between expanded clay and GVL, you need to lay all the necessary communications, for which you need to use special corrugated tubes.
- Begin the installation of gypsum fiber materials. Installation of a medium-sized gypsum board base floor. It is a simple and quick process for laying small to medium-sized slabs to be fastened together with folded edges.. If the ends of the slabs are not folded, then simply lay the slabs in two layers so that the joints of the slabs of the first and second layers do not coincide. Most often, slabs with a thickness of 1 to 2 cm, rectangular 1.5 mx 1 m are used..
- Underfloor heating, which is gaining more and more popularity today, is mounted between GVL-plates and the topcoat..
- After the GVL-plates are laid, it is necessary to putty the seams and places where the screws are screwed. In kitchens and bathrooms, the joints between the sheets need additional waterproofing.
- A day after the end of work with gypsum fiber board, you can begin the final finishing of the floor, including the laying of tiles..
For work you will need the following tools and materials: a knife or a hacksaw, tape measure, mounting glue, various spatulas (notched and ordinary), sealing tape, construction tape, level, self-tapping screws, special screws for gypsum fiber board, dowels. Will facilitate and speed up the work of the jigsaw and drill.
Tips & Tricks
We present the most relevant recommendations from experienced GVL installers:
- All calculations for the amount of materials must be performed in advance, this will help to avoid unnecessary expenses, because GVL sheets are not cheap material.
- Before purchasing slabs, we recommend inspecting them for cracks and chips. Cracked sheets cannot be used in construction, and chips will cause you a lot of trouble when adjusting the slabs to each other..
- When buying glue, make sure that it is suitable for working with GVL. Otherwise, the material can be spoiled..
- If tiles will be laid on the floor covered with gypsum plasterboards, we recommend that you take a three-day break between installing the gypsum fiber board and laying it.
- Be sure to tie the slabs before cutting the seam edge adjacent to the walls..
- Valuable advice – coat the folded joints with glue, so the “lock” connection will become much more reliable. If there is too much glue and it “comes out” from the seams, then try to remove the excess as soon as possible – you can use a sponge or dry cloth.
- If GVL-plates are laid on the floor in two layers, then we recommend taking small-format plates for the lower layer, and standard ones for the upper one. Such a floor will turn out to be more reliable and strong, it will not “breathe”.
- The tile adhesive that you will apply to the GVL sheets dries very quickly. Do not smear the entire surface at once.!
- If you use GVL for a floor with tiles, then it is advisable to prime the floor before laying the tiles. After priming, check if the surface is breathing..
- If it is not possible to use expanded clay for insulation, then give preference to mineral wool.
- Putty “Fugenfüller GV” is best suited for finishing the joints of gypsum fiber boards.
- Wet rooms require the installation of only moisture-resistant GVL sheets. Ordinary slabs, of course, will also last for a while, but this will be a temporary measure, and they will have to be replaced soon..
- If the main floor is complex and uneven, then sometimes you have to lay not two, but three layers of GVL-plates. True, in this situation you need to think about the additional installation of a lag, because the floor will become much heavier.
- Construction and repair work using gypsum plasterboard, including repair of floors, can be carried out both in private and in apartment buildings..
- GVL slabs can be an excellent replacement for traditional wooden floors..
- GVL-sheets for the floor are perfect for the construction of warm water or electric floors.
- Seams between panels in a bathroom or kitchen must be treated with high-quality waterproofing mixtures, since water falling on the floor should not get between the plates.
- GVL-plates are suitable for pouring the popular “liquid floor”, as they are able to withstand a serious load.
See below for more details.