How to insulate a house
About basalt wool and polystyrene thermosystems
The insulation of a house is a particularly important topic, especially in the current context, when we have to be careful that the investment we make in the purchased home really brings us long-term benefits. Of course, the energy and heating costs, as well as other maintenance and repair costs, will depend on the way it is built and covered, if durable and resistant materials were not used. Insulation is made on multiple layers and for a maximum efficiency it is recommended to properly insulate the walls, roof, floor, as well as door and windows. Many of those who come to the chapter of house insulation do not know what materials would be advisable to use, which is why we have centralized some useful information on this subject, detailing in particular about wall insulation.
Why house insulation is important
Insulation will help you maintain the desire temperature in your house throughout the year, protecting it from cold in winter and excess heat in summer. Insulation is also useful to reduce noise pollution. A well-insulated home is very energy efficient and will need very little additional heating and cooling.
Wall insulation with basalt wool
The insulation materials available on the market have some common features, namely, wool-like structure that traps small amounts of air. The mostly common used for wall insulation are basalt wool and polystyrene. Each of them have advantages in use, but also weaknesses.
In what concerns mineral basalt wool, it is considered the best method of wall insulation, being both sustainable and natural. It is used only on the outside of the walls and has a minimum impact on the environment, maximizing people’s safety and well-being. In addition to being resistant to fire and temperatures over 1000 °C, it has thermal properties, saving energy by maintaining an optimal internal temperature, but also a healthy climate, because it allows the water vapors to circulate to the outside for an optimal humidity inside. Although the faces of basalt wool panel have different degrees of rigidity (soft face inwards and hard face outwards), it has an aesthetic appearance when part of an assembly. More than that, on the outside, the hard face repels water while the soft one allows water to come out.
In terms of costs, basalt wool is more expensive than polystyrene, because it requires careful handling and installation. Being robust and heavy, basalt wool panels are difficult to transport, which involves higher selling costs. The adhesive compatible with basalt wool, as well as the fixing accessories, have high prices, which increase as the layer of basalt wool chosen for insulation is thicker. Also, in terms of application, specialized personnel are needed to handle and mount it correctly, since if it is not applied according to the rules established by the manufacturer, spaces will appear between the plates at the joint. Experts in the installation of basalt wool tiles know how important it is to fix them to the millimeter, especially since foam is not added between them to fill the gaps, as in the case of polystyrene insulation. While it insulates thermally, it also insulates acoustically, blocking, absorbing and improving the quality of sound reproduction.
Walls insulation with polystyrene
There are two types of polystyrene, extruded and expanded, both of which are much easier to transport and handle than basalt wool, because it is not a heavy material. The extruded one is hard and resistant to compression and compaction, managing to support a very large mass without degrading. This type of polystyrene is usually used in foundation slabs and floors. Expanded polystyrene is simple to install (without the risk of skin irritation if gloves are not used, as with basalt wool) and is a viable option for most insulation needs. The polystyrene will retain the heat in winter and reflect it in summer, but will not have an optimal ability to transport moisture, which can generate mold growth.
The polystyrene insulation used in constructions is fireproof, so it will not burn with a flame. Nevertheless, in case of very high temperatures specific of a fire, it will melt. It should also be taken into account the fact that the polystyrene can erode the sheathing of electrical cables, which can increase the risk of a fire. Moreover, when applied externally, it does not withstand trauma well, disintegrating easily, being an attraction for household rodents. On the other hand, the costs for polystyrene panels and accessories necessary for installation are lower than those for mineral basalt wool.
The role of the ventilated facade in insulating the house
Although both types of insulation are sensitive to trauma, using a ventilated facade can offer protection by its general integration and the long-lasting nature of the underlying decorative layer. It will behave like an impenetrable and dense layer, which will act as a barrier against any factors that could degrade it. The ventilated facade will add to the thermal insulation of the house, ensuring a high energy efficiency of the building.
The thermal properties of this system are based on the basic principle of the “chimney effect”, resulting from leaving an airspace, several centimeters deep, between the perimeter wall of the building, on which insulation has been applied, and its external face. The change in air density inside the air gap, due to the heat generated by the outer shell, forces the air to move upwards and triggers a flow of natural ventilation from the bottom up.
All the houses and apartments of h4l neighborhoods are insulated with mineral basalt wool, ventilated facades being applied to them, in order to generate minimal energy consumption and to be in agreement with the sustainable principles on the basis of which they were designed and built. Now that you know something about each house insulation system, which one would you go for?
This article also exists in Romanian here – Cum să izolezi o casă – Despre termosisteme din vată bazaltică și din polistiren