Thermal insulation of the ceiling with glass wool, the features of such insulation, its disadvantages and advantages, the preparatory stage of work, insulation installation technologies. Insulating the ceiling with glass wool is one of the ways to save heat in the premises of a house or apartment. Its use allows you to reduce the cost of heating your home by eliminating the leakage of heated air through the ceiling or roof. This article is about the features and various methods of thermal insulation of a glass wool ceiling structure.
Features of thermal insulation of the ceiling with glass wool
Glass wool is an inexpensive and therefore affordable insulation for many. Its low cost is due to the cheap components from which this material is made. This is mainly industrial waste, in this case, glass breakage. The raw materials for the manufacture of glass wool can also serve as sand, soda and mountain minerals - limestone and dolomite.
The high efficiency of insulation with glass wool is evidenced by the fact that for decades the technology of its production has practically not changed. If desired, this material can be used in conjunction with other more expensive thermal insulation products, thereby obtaining certain economic benefits.
Insulation is marketed as slabs or rolls. For insulation of the ceiling with glass wool, it is more convenient to use rolls, for walls - slabs. In any case, both of them can create a monolithic heat-insulating layer on the enclosing structures without the formation of any cold bridges.
The thermal insulation properties of glass wool are determined by its density. For insulation of the ceiling, it should be 20-50 kg / m3… If insulation is required to be laid on the ceiling from the side of the roof, insulation should be purchased with a higher density than for work from inside the room.
Installation of glass wool has a specific feature. It is associated with the separation of fibers from the material during its laying. Unlike basalt wool, the smallest glass fibers are shaped like needles that can easily penetrate under clothing, into the lungs and into the eyes. This is especially dangerous for the respiratory system. Small points of glasses, getting into the lungs, remain there for a long time and can cause chronic diseases. Therefore, it is imperative to work with glass wool in tightly buttoned overalls, goggles, gloves and a respirator.
Pros and cons of glass wool ceiling insulation
The main advantage of glass wool ceiling insulation is a successful combination of low cost and high efficiency.
In addition, other undoubted advantages are inherent in such thermal insulation:
- Ease of installation and suitability of the coating for repair - any part of the insulation can always be replaced in case of damage.
- The possibility of combining thermal insulation made of glass wool with another type of insulation, depending on the engineering solution and the needs of the building envelope.
- Glass wool is environmentally friendly due to its chemical inertness. An exception are cases of damage to the skin from exposure to the fibers of the material.
- Thermal insulation is fire safe. Glass wool cannot become a source of fire in the room, and if it has arisen for another reason, the melting insulation does not emit harmful substances into the air.
- Insulation is easy to install compared to many other insulation materials. Thanks to this, the use of glass wool saves time for builders and makes it possible to conduct self-repair by home craftsmen.
- Glass wool is easy to transport: thanks to its elasticity and low weight, rolls of material can be easily delivered to the place of work, even in a passenger car.
When choosing glass wool for thermal insulation of the ceiling, its disadvantages should also be taken into account:
- The danger when laying such a heater for the eyes, skin and respiratory organs. Therefore, the need to use protective equipment makes glass wool a problematic material for work.
- Compared to other insulation materials, the strength of glass wool is low. It breaks and can shrink over time, reducing its original volume.
- Glass wool insulation is hygroscopic. For this reason, it quickly absorbs moisture, which is especially typical when insulating floors.
- The density of the material is low, therefore, for reliable insulation, glass wool has to be laid in two layers.
Preparatory work before insulation of the ceiling
Before insulating the ceiling with glass wool, it is necessary to clean the crumbling areas of its surface, treat the structure with a penetrating primer, antiseptic and perform a protective insulation of the insulation.
If you plan to install lamps on the ceiling, you need to lay electrical wiring taking into account their location. The supply wires of the lamps should be led out in loops so that after the installation of the thermal insulation and subsequent finishing work, the lighting equipment can be installed without any problems.
When placing the ceiling between rooms, one of which is unheated, take into account the movement of the dew point towards the warm surface. To prevent condensate from getting on the future insulation, a waterproofing membrane should be glued to the prepared ceiling or fixed with brackets using a construction stapler.
To work with glass wool, it is recommended to stock up on such materials and tools: insulation in mats or rolls, plastic wrap and glassine, scissors or a knife, tape measure, pencil, stapler, thick overalls, goggles, gloves and a respirator.
Glass wool ceiling insulation technology
In urban apartments, ceiling insulation is most often required by residents of the upper floors. The heated air, according to physical laws, rises up and tends to go into the cold attic space. External and internal insulation of the ceiling helps to prevent this process. In the first case, thermal insulation is performed from the side of the attic, in the second - from the inside of the dwelling. When insulating from the inside, it is necessary to take into account the loss of the ceiling in height up to 200 mm due to the thickness of the thermal insulation and decorative finishing.
Thermal insulation of the ceiling outside
This is the most convenient and high-quality type of ceiling insulation, provided that you have access to the attic of the house. If the operation of the attic is not planned, including walking on it, you can roll rolled glass wool over the ceiling in 2 layers, placing them in a mutually perpendicular direction.
In the case of using the attic space for servicing the communications passing through it, as a warehouse or for seasonal residence, the ceiling insulation should be done differently. In this case, glass wool is placed between the lags with a section of 50x150 mm, fixed to the edge. The step of the beams is chosen such that the insulation is located in the cells tightly, without forming voids. After laying the thermal insulation on it, you need to make a wooden flooring, fixing the boards with nails on the logs.
In both cases of external insulation, when laying glass wool on the ceiling, it should be covered on both sides with a vapor barrier film, taking into account the hygroscopicity of this thermal insulation.
Ceiling insulation from the inside
Insulation of the ceiling from the inside of the room can be done with and without lathing. Let's consider both of these cases.
The first of them provides for fixing glass wool on the surface of the structure in special cells of a wooden lathing. It can be made from wooden blocks with a cross section of 50x50 mm. The bars are attached to the ceiling with dowels. The width of the obtained lathing cells should be 3-4 cm less than the size of the slab or insulation roll. In this case, the thermal insulation can be tightly packed between the frame bars, without fear that it will fall out before the next work on the ceiling begins.
The installation of wooden lathing on the ceiling should be constantly monitored by the building level. All bars should be located strictly horizontally and form a single plane of the structure. After installation, the insulation should be covered with a layer of protective vapor barrier material. Such a membrane is attached to the wooden battens of the sheathing with staple staples. The joints of the film canvases should be sealed with construction tape.
After installing the frame, laying glass wool in it and making a vapor barrier layer on top of the insulation, the finished ceiling structure can be sheathed with any suitable finishing material: plywood, plasterboard sheets, plastic panels. Their fastening is carried out with self-tapping screws to the wooden ceiling lathing. It is recommended to leave a ventilation gap of 3-4 mm between the finish and the insulation to drain condensate from the surface of the vapor barrier material.
Before fixing the glass wool on the ceiling without using a crate, the surface to be insulated should be thoroughly cleaned of delamination and greasy stains, and then a layer of coated polymer waterproofing should be applied to it. In addition to performing its main function, it will increase the adhesion of the base with the adhesive on which it is planned to fix the insulation.
After the waterproofing layer has dried, an adhesive should be applied to the ceiling and glass wool slab and the insulation should be pressed to the surface for a couple of minutes. The rest of the boards are glued in the same way. During installation, they should be tightly laid in relation to each other, avoiding the appearance of voids. After laying solid slabs, the remaining sections of the ceiling must be filled with fragments of insulation, previously cut to size. After gluing, each one-piece product should be additionally fixed to the ceiling using disc dowels, based on the calculation of 5 pcs. on the stove.
After fixing the glass wool on the ceiling with glue and dowels, the finished surface should be covered with a layer of special glue. It is necessary to press the plaster mesh into it, placing it over the entire area of the insulated surface. After the glue hardens, the mesh, which performs the reinforcing function, will make the protective outer layer of thermal insulation monolithic and durable.
After a couple of days, the ceiling insulated in this way can be plastered, putty, painted or any other finish can be performed on it, including the installation of a stretch canvas.
How to insulate the ceiling with glass wool - watch the video:
It is possible to cope with the thermal insulation of the ceiling with glass wool on your own, without involving hired workers, who are not always conscientious. This will save your family budget. You can buy high-quality thermal insulation in a popular hypermarket, a good product will always have a homogeneous structure, be in neat packaging and have a certificate of conformity.
