If you focus on the cost of heat-insulating materials on the market, then the following types of mineral wool made from:
- fluffed basalt fibers (stone wool);
- fiberglass (glass wool);
- molten slag (slag).
It should be noted that according to its technical characteristics, slag is almost completely consistent with basalt materials, but due to the high hygroscopicity in housing construction it is very rarely used. In addition, fluffed slag fibers are able to enter into a chemical reaction with water, forming an acidic solution that destroys building structures.
Therefore, a comparison of the more commonly used insulating products, i.e. from basalt fibers and glass wool.
Advantages and disadvantages
In order to justify the difference between mineral and basalt wool was, consider their technical and operational characteristics, cost, hygroscopic indicators and installation method.
Basalt wool
For the manufacture of stone wool, basalt (volcanic rock) and gabbro (granite grade) are used. The stones are crushed and melted. After that, the liquid lava is blown through a lattice with small holes to obtain fine fibers with a diameter of 4-12 microns and a length of up to 16 mm. The resulting fibers, solidifying, form a layer of loose material into which a binder in the form of formaldehyde resin is added, after which plates up to 6 meters in length are formed.
The coefficient of thermal conductivity of the material is in the range from 0.035 to 0.042 W / (m * K) and depends on how closely the fibers are arranged. Operating temperature range from -190 ° C to + 1000 ° C. The heater does not burn and does not absorb water. It has excellent soundproofing properties.
In list positive characteristics of thermal insulation from basalt fibers should be called:
- long service life reaching 50 years;
- resistance to high temperature and an open flame;
- almost zero hygroscopicity;
- excellent thermal insulation properties;
- high level of absorption of sound vibrations;
- resistance to chemically active substances;
- high elasticity, preserving the shape and size of the plates;
- a possibility of use for external and internal works;
- light weight and easy installation;
- environmental cleanliness;
- does not attract rodents and insects;
- does not serve as the basis for the appearance of fungus and mold.
At the same time, basalt heaters have a number of significant disadvantages:
- high cost due to high energy costs for production;
the presence of mounting joints that reduce the effectiveness of insulation;
the release of large amounts of dust during cutting and styling.
As you can see, basalt wool has more positive characteristics than negative ones. But the relatively high cost often keeps the buyer from choosing this thermal insulation.
Fiberglass Mineral Wool
The raw materials for the manufacture of glass wool are glass wastes, to which a mixture of quartz sand, limestone, dolomite, borax and soda is added. The volume ratio of glass and mixture is 4: 1.
Broken glass and additives are sent to a furnace for melting at a temperature of 1400 ° C. The molten mass is blown under pressure through a fine lattice to obtain fine fibers with a length of 15 to 50 mm and a diameter of 3 to 15 microns.
A binder is added to the layer of the obtained yarns, which connects the thin fibers to each other. Moreover, the longer the glass filaments, the more elastic and durable the insulation will be.
All this hot fiber mixture falls onto a moving conveyor, where a layer of glass wool is formed, the thickness of which depends on the speed of the line. From the insulation tape obtained on the conveyor, plates are cut or rolls are rolled up.
The thermal conductivity coefficient of mineral wool is from 0.038 to 0.046 W / (m * K). Extreme working temperature + 450 ° C. The material is hygroscopic and can be used only for internal work. For outdoor use and in damp areas, it requires additional protection against moisture.
In list merits mineral wool insulation should be called:
- low cost;
- low weight, which allows insulating weak structures;
- environmental cleanliness;
- good thermal insulation properties;
- ease of installation;
- incombustibility;
- resistance to fungus and mold;
- convenient transportation.
In list cons:
- high hygroscopicity;
- a change in shape and a decrease in thermal insulation properties when wet;
- service life no more than 10 years;
- the need to use eye protection and respiratory organs during installation;
- attractiveness for rodents;
- low resistance to aggressive chemicals.
As you can see, glass wool has a number of serious drawbacks that should be considered when choosing a heater. However, due to the relatively low price, it remains popular with buyers.
Performance Comparison
In order to reliably decide which is better, a basalt plate or mineral wool, it is necessary to compare the most important indicators, among which we will include:
- cost;
- heat-insulating qualities;
- gyroscopicity and vapor permeability;
- durability;
- environmental friendliness;
- noise insulation indicators;
- fire safety;
- ease of installation;
- attractive to rodents and resistant to mold.
Having determined these criteria, it will be possible to conclude which insulation is better and what to choose for each particular case.
Which is cheaper
Mineral wool is sold at a price of 1200 to 1400 rubles / m3. The cost of basalt insulation is from 1450 to 2250 rubles / m3. Installation prices are the same. In addition, the laying of plates is not at all difficult to perform on their own.
Turns out that mineral wool is 20-25% cheaper than basaltthat, with a limited budget, can be a critical factor. However, it should be noted that cheaper material has worse performance and this will lead to serious financial losses in a few years.
Which is warmer
The thermal conductivity coefficient of basalt mats is 0.035-0.042 W / (m × ° K), glass wool is 0.038-0.046 W / (m × ° K). That is, for this indicator both thermal insulation materials are almost identical. Therefore, the choice of thermal conductivity coefficient simply does not make sense. In addition, as practice has shown, most manufacturers produce their products with a thermal conductivity coefficient below the average declared level.
Hygroscopicity and vapor permeability
The water absorption rate of basalt mats is close to zero. Glass wool actively absorbs moisture, while losing thermal insulation properties and changing its original shape. The vapor permeability or the ability to pass air is the same for both heaters. But it should be noted that if mineral wool mats are wrapped with a plastic film to protect against moisture, then its vapor permeability will completely disappear.
According to these parameters, basalt insulation should be recognized as the best.
What is more durable
In absolutely dry conditions glass wool can last up to 30 years. After that, due to crystallization processes, the material will collapse. But, as reality shows, mineral wool insulation rarely lasts more than 10 years. The main reason is the absorption of moisture from the air and, as a result, the acceleration of the crystallization process.
Manufacturers stone wool claim 50 years possible operation, although the material began to produce a little more than 25 years ago. There is no real data yet, as there is no information about forced replacement of the insulation.
Buying more expensive basalt mats may be more profitable, because the material does not require replacement for a long time and does not lead to additional costs in the long term.
Environmental friendliness
There are no harmful components in both materials. However, 3-4% formaldehyde resin is present in binders. Therefore, a number of experts consider both heaters to be potentially dangerous to humans, not taking into account that formaldehydes begin to emit up to 2.5% of harmful substances from their volume only if they heat more than 30 ° C.
Therefore, we can confidently conclude that in real conditions both heaters can be used in housing without restrictions.
Soundproofing
Both that and an arch material effectively damp out sound vibrations. In basalt, this figure is higher, but not significantly. Therefore, this indicator can not be taken into account when choosing a heater.
Fire safety
According to fire safety indicators, both materials are non-combustible and can only decay at temperatures above the maximum permissible.
What is easier to mount
The styling technology itself is exactly the same. However, when working with glass wool you will have to worry about protecting your eyes and respiratory organs. At the same time, basalt mats also emit dust during work, although, according to experts, it is safe for health. The installation technology for the example of the ceiling we described here.
Which is better against mold
Both heaters do not contribute to the development of mold and fungus. But basalt material does not attract rodents at all, but they live in glass wool very willingly.
What and in what case is used
Having considered the main indicators of materials, we can draw the following conclusions:
- Glass wool is quite suitable for warming dry rooms and building structures to which moisture does not enter. Protection from a plastic film will reduce vapor permeability to zero and mustiness appears in the room.
- Basalt cotton wool can be used in any conditions, even when warming baths and facades in a "wet" way.
For wall insulation in frame houses and concrete surfaces, it is recommended to lay cotton wool with a density of at least 100 kg / m3. In attics and attics, the density should be lower.