Properties
Contenido
Las placas de cartón yeso se fabrican en una anchura estandarizada 1,20 metros y diferentes longitudes de 2, 2,5, 2,6, 2,7, 2,8 y 3 metros. Los fabricantes pueden cambiar la longitud de la placa a las dimensiones del cliente para pedidos suficientemente grandes. Se comercializan en diferentes espesores (10, 12,5, 15 y 18 mm), aunque para grandes espesores es habitual superponer varias placas de pequeño espesor, colocadas «a mata juntas».
Los tableros de yeso poseen un núcleo cortafuego encapsulado en grueso papel, generalmente papel reciclado, de acabado natural en la cara frontal y de un papel duro en la parte posterior, lo cual permite maniobrar y cortar fácilmente, con cúter o navaja, facilitando así su instalación y la aplicación inmediata de cualquier tipo de recubrimiento o acabado (pintura, pasta, azulejo, etc.) Las juntas (uniones entre las placas de tableros de yeso) tratadas correctamente durante el proceso de instalación evita el agrietamiento causado por movimientos de los bastidores.
Además de las placas de cartón yeso para uso normal, existen placas modificadas para usos especiales.
Fire resistance
Plasterboard is not flammable, that is, it does not catch fire even when exposed to direct fire. It is made of hydrated calcium sulfate (CaSO + HO) and other compounds. When exposed to fire, calcium sulfate loses water molecules through evaporation, slowing the spread of fire for several minutes. When the calcium sulfate dries or dehydrates, it disintegrates (crackle) and the plate crumbles, finally allowing the fire to pass to the other side of the wall.
It needs to be installed correctly to serve as a fire barrier as any perforation or small space will allow fire to pass through even when the board has not disintegrated.
A thicker plate resists the attack of fire for longer than another of the same type but thinner. Two plates installed one on top of the other also offer greater fire resistance; in these cases it is recommended that the splices be alternated to offer greater resistance. There are special versions made with compounds that resist fire for longer.
According to what is published in the manual [1] of USG or in Spain UNE EN 102.043, certain specifications are needed for the correct assembly of a structure fire resistant, resistance degrees range from 30 minutes to several hours, the panels to be used must comply with the required regulations.
For a resistance of 30 minutes, two 5/8 inch thick panels are used on each side of the structure made up of an upper metal channel, a lower channel and metal posts of minimum 25 gauge, spaced at a maximum of 24 inches.
For walls with fire resistance of one hour, the same metal structure and type x drywall panels with a thickness of 5/8 that are more compact in their composition are used on each side of the metal structure.
By increasing the number of drywall panels adhered to each side of the structure, its resistance to fire is increased, in order to safeguard the integrity of the people who occupy the spaces protected by these limitations.
Acoustic insulation
Plasterboard has a very low mass, so by itself it does not provide great acoustic insulation. This insulation is usually obtained by placing an absorbent material placed inside the panel chamber, or between the backing plate and the support element.
Sound propagates through solid materials such as metal structures that support the plates or through the gaps left on the ceilings. Therefore, it is important that the anti-sound treatment be a joint project of walls, structures and ceilings to have greater effectiveness.
Thermal insulation
Gypsum boards alone are not good temperature insulators. Due to its thin thickness, heat or cold easily penetrates through the gypsum board resulting in uncomfortable temperatures inside the built space. To obtain good thermal insulation, it is necessary to cover the inside of the walls or ceilings with thermal insulation made of fiberglass, solid foam boards or other materials.
Moisture resistance
There are moisture-resistant plasterboards that are used in humid places such as bathrooms, cleaning rooms, kitchens, etc., where there may be areas exposed to occasional splashes. Moisture-resistant gypsum boards are made from treated paper that slows water absorption and fungal growth. In addition, the core of the plate contains special additives so that they do not stain or disintegrate. The plates are designed to withstand occasional splashes of water but are not recommended to be exposed to rain or in direct or constant contact with water or steam such as showers, showers or saunas.
It can be installed in bathrooms and kitchens at home without any problem as long as it has an anti-mold coating and must be removed and replaced. For decoration, tiles can be glued to the same wall but it must be done with a special adhesive for that type of system such as specific glue mortars for PYL.
Other applications
The plates can have barite coatings or lead sheets that are screwed to the panel to be used in radiological rooms in hospitals and clinics, to serve as a barrier against ionizing radiation. They can also be covered with fiberglass sheets that are completely washable, for industrial kitchens or food factories.
The resistance of a plaster wall is strong because it has three metal posts installed on the back. Its design allows you to hang pictures, kitchen furniture. shelves, screens, etc., using the appropriate plugs. The wall is easier to repair if it is damaged.