When choosing a thermal insulation material for a house, apartment, or cottage, homeowners face many ambiguous comments and recommendations. It is not easy for a non-specialist to distinguish fiction from the truth, especially since the authors and storytellers of myths are sometimes very eloquent and convincing. To dispel the fog of doubts and dot the "i" on insulation choice, we have collected some frequently occurring statements and decided to explain why they are wrong.
Myth #1: It's better to insulate with mineral wool in sheets
The basis of this myth is the misconception that a less dense material (and rolls are made of lightweight wool) is inferior to a denser one in terms of thermal insulation characteristics. This is a fundamental error, contrary to the laws of physics. The fact that the main and the best insulator is air. The more it can hold the material, the more effective it is as an insulator. Lightweight mineral wool, sold in rolls, has a low density, so between the fibers fit more air.
The figures confirm the effectiveness of this material. For example, the density of lightweight quartz wool ISOVER (14-20 kg/m3) is half as much as similar thermal performance boards made of rock wool (30-60 kg/m3). This effect is achieved due to the structure of quartz wool: the length of its fibers is 25-30 cm with a microscopic thickness of only 3.5-5 microns, which means that the material becomes airy.
The second feature is also due to the structure of the fibers: with such a ratio of thickness and length, they are highly elastic and form a flexible, springy structure. Due to this, quartz insulation, cut with a small (about 5 mm on each side) margin, slightly compressed and laid in the spaces between the elements of the crates, straightens and fills the entire room, leaving no thermal bridges. Unlike rigid boards, roll insulation does not form joints and forgives installation errors - it can be moved from one structure to another without breaking and deformation.
Myth #2: the ability of mineral wool to hold in inclined and vertical structures
To prove that the insulation does not slip and requires particular fixation, Saint-Gobain sent samples of ISOVER quartz wool to the Tver Institute of Car Building for testing. The material was subjected to a series of vibration tests with a frequency of vibrations up to three thousand beats per minute on a test bench, creating conditions similar to those of operation for 50 years. The test results showed that the quartz wool would not slide down even from the vertical surfaces and would not crumble over the years. Therefore, as a result of the tests, it was approved as insulation, including company trains. For the same reason, roll quartz wool will be a reliable solution for all types of insulation and soundproofing in individual construction, especially on pitched roofs.
Myth #3: about the lifespan of mineral wool
Once upon a time, back in the Soviet Union, there was widespread cheap insulation of low quality - glass wool. It was formed by short and thick (up to 500 microns) fibers, more like needles. Over time, they crumbled, and this is - the first source of myths about the short life of mineral wool. Today, this material is not produced and not used.
The second reason for the erroneous judgments is the properties of rock wool used in industrial construction. As a result of getting wet, it loses its original structure and needs to be replaced.
On the other hand, quartz wool can repel moisture, so even in the event of emergencies, the homeowner will not have to spend money on new insulation. As tests have shown, its lifetime is not less than 50 years. Thus, one insulation is enough for the entire period of operation of a private house.
Myth #4: About insulating a pitched roof home
The myth that rolled mineral wool needs additional fasteners again brings to mind the elastic properties of quartz wool due to the length and elasticity of its fibers. Experts call this technology Formostability: insulating material takes the form of a cell in which it is placed and keeps it throughout its lifetime, with no need for fasteners. The main thing is to remember to leave an allowance of 5 mm on each side when calculating the width and to cut the wool so that the material can be compressed during installation.
Myth #5: About the speed and methods of building with insulation
It is not uncommon to hear from theorists that insulating the roof and walls with rolled mineral wool is inconvenient. This statement contains a factual error. Practice shows that installation of roll insulation on the walls is two to three times faster than the pre-cut or plate. The explanation is simple. If the room's height is to install two or three plates, securing and adjusting each of them, the roll is enough to cut vertically, fix the top, and roll down.
In addition, when installing the boards, you must carefully control the quality of the joints to avoid the appearance of thermal bridges (see above). In some cases, the joints are additionally insulated, and often the insulation is mounted in two layers, with a scattering. Using rolls avoids such complications. In addition, lightweight roll insulation based on quartz wool fills the entire space between the elements of the crates, tightly adjacent to it without any additional action and fasteners.
Similar measurements of labor costs for insulation of floors and pitched roofs showed that in the case of roll, insulation material from quartz installation is three to four times faster since, in this case, one roll is often the length of three or four boards.
Consider another fact - the greater insulation thickness - the more time you can save on work on its installation. For example, the layer's standard thickness underlay thermal insulation is 200 mm for most Russian regions. Since the plates often have a thickness of 50 mm, putting them in four layers is very time-consuming. Roll insulation is much easier: its thickness is 100 and 150 mm, so you need to mount only one or two layers. The same applies to the thermal insulation of facades. At the same time, quartz wool also more effectively retains heat.
Myth #6: The cost of insulation
Buying the cheapest pack on the store shelf will not save you money. The fact is that in the same size pack, different manufacturers supply different amounts of m2 of material. This is because one type of mineral wool can shrink several times while another is not. Not knowing this, many people either compare the price per pack of insulation or count the volume of the packaged compressed rolls and compare it to the cubature of the boards. Then how to properly compare prices per square meter of unfolded material. For example, roll insulation ISOVER Warm House thickness of 100 mm based on quartz wool will cost less than 60 rubles per square meter, and the same thickness and thermal insulating properties of the plate material based on basalt wool - about 160 rubles per square meter. The difference is very substantial. In addition, you will not need to overpay for scraps when insulating with rolls: they are much less than the plates.
You should also take into account the benefits of delivering the materials. Rolled quartz wool insulation is more convenient to load and transport alone. Given that it is strongly compressed in the package, it can even be placed in a personal car, saving on shipping. For the same reason, on the lot, in an apartment, or a utility room, a much smaller area is required to store the rolls. In addition, they are much more convenient and faster to carry and unload. The number of approaches to the material to the car and back or up to the floor is significantly reduced.
Modern quartz mineral wool is a versatile, durable, and reliable insulation material with several advantages, especially significant for the owner of private houses and apartment buildings. Using products suitable for specific tasks, you can qualitatively insulate your house for many years while doing it yourself and significantly save on the material itself and shipping and heating bills.