Technology and nuances of laying gypsum fiber boards on the floor under the tiles

When preparing floors for tile installation, gypsum fiber boards are an adaptable and sensible option for building a sturdy foundation. They offer a stable, smooth surface that makes it more likely that your tiles will stick well and endure over time.

Due to its excellent results and ease of use, this method is especially well-liked. Whether you’re installing new flooring or working on a renovation project, knowing how to lay gypsum fiber boards can have a big impact on how things turn out.

We’ll lead you through the main procedures in this guide and emphasize the crucial information to remember while working. You’ll be well on your way to attaining a polished finish with the appropriate technique.

Characteristics and features of the material

Numerous factors set gypsum fiber panels apart from other sheet goods, including:

1. Strength. Homogeneous structure provides high performance. This is explained by the composition: gypsum and cellulose fibers, which provide a reinforcing effect.
2. Viscosity. Elements can be processed in various ways: sawing, milling, etc. ., this will not damage the structure and deform parts. It is due to this that a good result is achieved when installing a warm floor.
3. Fire safety. The products do not support the spread of fire, which allows you to lay the slabs on various communication systems.
4. Low thermal conductivity. The resulting gypsum fiber surface can be used as additional insulation. But this significantly complicates the process of installing a warm floor, since the system has to be literally built into the gypsum fiber sheets.
5. Wide range of applications. The boards are suitable for concrete and wood bases, as well as for installing dry screeds. The sheets are relatively light in weight, so they do not exert a significant load on the bases. The material can be laid with your own hands without the involvement of specialists.

The two primary categories of gypsum fiber products used for horizontal bases are the standard version and GVLV, or moisture-resistant gypsum fiber board for floors. The end floor covering will be dependable and long-lasting, provided the right variety is selected.

Water-resistant flooring is commonly used in humid bathrooms and kitchens and is the best option when installing a heating system.

A practical and effective way to create a stable, moisture-resistant, and even surface for tile installation is to lay gypsum fiber boards underneath the tiles. To guarantee the longevity of the tiled floor, this method entails exact preparation, proper board placement, and careful joint sealing.

Installation of gypsum fiber board flooring

Technology assumes that specific small-sized products with the following dimensions will be used for installation: thickness 12.5 mm, width 100 or 120 cm, and length 150 cm. Working with such dimensions is not only much more convenient and easy, but it also eliminates a significant amount of trimming.

First, the surface needs to be ready:

1. The base is cleared of all unnecessary things, the room must be free. To obtain a high-quality result, it is advisable to completely remove the old coating.
2. The cracks are sealed with cement mortar. Particular attention is paid to the junctions of the walls and the floor.
3. The surface is cleaned of construction debris.

The sheets must also be left at room temperature for a full day.

Preparation methods

1. The dry method doesn’t require complicated procedures, so you can obtain the base in a reasonable amount of time. Several installation choices exist, contingent upon the surface imperfections:

• If there is no deformation, gypsum fiber board can be glued directly to concrete, but the surface must be primed first.
• With minor differences (3–4 mm), an intermediate layer of cardboard or foam is laid on the floor.
• With deviations of about 1 cm, a layer of expanded clay is poured. It is used when there is no need for additional thermal insulation of the base.
• If the collapse exceeds 20 mm, a prefabricated structure is created: an expanded clay layer supplemented with a foam plastic spacer.

2. The wet method uses specialty "repair" mixtures for leveling, but these can be substituted with less expensive cement compositions by adding modifiers and sand. But because it takes longer to prepare, this method is not as good as bulk options.

You should know this! Wooden floors can also be cleaned using the dry method while working with concrete, but they must be handled extra carefully.

Preparation of the base from logs

It will take longer to complete this process than backfilling. The wood needs to be properly dried and treated with protective compounds before it can be installed with extreme precision. Jumpers are used to connect the elements to each other, and substrates are used to level the logs directly onto the walls and floor. This process is unique in that the gypsum fiber needs to be mounted on the created lathing rather than the base. A small section of timber fixed perpendicular to the logs is used for this purpose. It is possible to install bulk or solid thermal insulation in the ensuing gaps.

Procedure for installing gypsum fiber boards

Whichever preparation technique is selected, the slabs are laid in accordance with this scheme:

1. As a waterproofing, a polyethylene film with a thickness of at least 0.2 mm is laid on the base, which should go onto the walls. The material should be placed with an overlap of 15–20 cm to prevent the ingress of moisture and loose components. On a wooden floor, instead of a film, you can lay a universal vapor barrier.
2. A soundproofing tape is glued along the perimeter to prevent contact between the gypsum fiber sheets and the walls.
3. The surface is leveled using a suitable method.
4. Then you can lay gypsum fiber. It is recommended to lay it in two layers. To avoid unnecessary expenses, the first layer is created from large-format parts, and on top of it, a floor gypsum fiber board with special chamfers is mounted. Such a structure will allow achieving greater reliability. The process should start from the doorway. The layers need to be glued together and fixed with self-tapping screws with a step of 20-25 cm.

It is noted that the small-format panel requires some initial setup: an electric jigsaw is required to cut the fold that will face the walls.

Be aware of this! Use gypsum fiber board-specific self-countersunk screws and glue that are double-threaded. If drywall alternatives or regular self-tapping screws come loose, it could damage the decorative coating.

Laying tiles on gypsum fiber

The supplies and equipment required for tile installation must be ready in advance. The following is the general order of work:

1. The room is marked out. For this, lines are drawn from corner to corner and between the center of adjacent walls. This will allow you to glue the products with the pattern adjustment.
2. The base is treated with a primer in two layers to ensure good impregnation, and dried.
3. The starting point of installation is determined and a layout diagram of the elements is created. Preliminary laying is often required.
4. Glue is applied to the surface. You can mix it yourself or buy a ready-made composition. The mixture is distributed over the base using a notched trowel.
5. The parts must be glued in a clear sequence, for this the element is pressed and, if necessary, tapped with a mallet with adjustment according to the level.
6. Parts are set at intervals, joints are formed using plastic crosses or a tile alignment system (TAS).
7. The extreme fragments are cut taking into account the gap from the walls.
8. The coating is left until dry, after which it is necessary to rub the seams with a special mixture of the desired shade. The composition is applied to the joints and distributed with a rubber spatula, the excess is removed.

The surface will last a long time if the process technology is not broken.

The installation of gypsum fiber boards beneath tiles provides a stable and long-lasting flooring base. Even though the procedure is simple, it needs to be done carefully to guarantee a level, stable surface that will adequately support the tiles.

You can accomplish professional results with a do-it-yourself project by carefully following the steps, which include precise cutting of the boards, secure fastening, and adequate subfloor preparation. This technique offers more stability and insulation in addition to extending the tile floor’s lifespan.

All things considered, knowing the subtleties of this technology can have a big impact on the result, resulting in a well-finished, long-lasting floor that will endure.

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