How to insulate the walls of a house from outside

For coziness and comfort to always reign in the house, the owners need to take care to insulate the walls of a house from outside in advance. In the winter season, the thermal insulation layer allows you to retain heat inside the premises, and in the summer it does not allow heat from the street to pass through. Let’s figure out what material it’s best to make it from and in what places.
Previously, people insulated their homes from the inside, which caused several problems. Now technology has changed, and houses began to be insulated exclusively from the outside. How to do it correctly and what materials are preferable to use?

Why external insulation and not internal

Surely many of our readers have noticed that in almost all private and apartment buildings the thermal insulation layer is located outside the walls, and not inside. Why is this so? The fact is that when insulating walls from the inside, there is a high probability of moisture accumulation between the floors. The harm of such a phenomenon is obvious – mold will appear, pockets of dangerous microflora will open, and the microclimate of the room will be disrupted.

Moreover, this is not just someone’s opinion from the outside, but a requirement of the current building regulations. According to this document, in double-layer walls, the thermal insulation layer should be located exclusively on the outside of the walls. The only exceptions are those cases when external thermal insulation cannot be implemented for technical reasons.

From a practical point of view, external insulation is more profitable in everything:

• increased protection of all structures – external finishing allows you to protect walls from the negative influence of the external environment
• saving useful space indoors – the area of ​​the rooms will not decrease by a single centimeter
• environmental friendliness – external insulation does not have any effect on the microclimate of the rooms.

In modern realities, many “experts” recommend that owners choose internal insulation – do not listen to amateurs, but study the issue yourself. If you plan to live in a private house for a long time, you should choose the option of exterior finishing.

What structures are insulated?

Insulating a house is an important stage in the construction process. The thermal insulation layer allows you to maintain natural temperature and humidity indoors, creating favorable living conditions. In summer, the inside of such a house will always be fresh and cool, and in winter, it will always be warm and cozy.

It is best to comprehensively insulate all external elements of the house. These include the base, floor, walls, roof, and various ceilings.

The skilled insulation installers in Wollongong expertly transformed the home, ensuring optimal energy efficiency and comfort for the residents.

Base

The plinth is the upper part of the foundation that protrudes above the soil. Most often, this type of construction occurs if use a strip or slab type of foundation. If there are piles at the base of the house, the plinth will be the walls located between the supports along the entire perimeter. The height of such a wall will not exceed 70 centimeters.

Ground floor floor

The first floor is considered the most vulnerable because it will be greatly influenced by frozen layers of soil. If it is not insulated, in winter the cold will penetrate inside the premises, and even carpeting will not save you from it. With slab foundations, this is a little easier, since there will always be a positive temperature under the floor. But even in this situation, it is better to play it safe and take care of the presence of a thermal insulation layer on the floor of the first floor. If the underground is in direct contact with the street, it is necessary to insulate it without any hesitation.

Walls

The walls are in most contact with the street – that is why so much attention is paid to the issue of their insulation. There are only two options here: if there is a frame, the insulation is placed between the floors, and in the case of monolithic structures it is placed on the outside. Here the material of the walls plays a big role – the choice of suitable thermal insulation will depend on it. We will return to this issue later.

Interfloor ceilings

Consider inter-floor ceilings to be structures connecting floors. Accordingly, for the first floor, such a structure will be the ceiling, and for the second floor, it will be the floor. Surely you will have a completely logical question – why should these floors be insulated at all since they are located inside the building? Yes, sub-zero temperatures do not have any effect on underfloor ceilings; the thermal insulation layer is placed here for other purposes. It provides high-quality sound insulation so that noise from one room does not reach another.

Roof

Surely everyone remembers from their school physics curriculum that warm air always rises. Now imagine: all the heat inside the room is drawn closer to the roof, which is additionally influenced by the cold from the street. What do we end up with? Enormous heat loss. To minimize them, insulate the roof even better than the walls. The minimum insulation layer should be 15 cm.

In summer, the situation is the opposite – the scorching rays of the sun fall directly on the roof, it overheats and evaporates its heat indoors. And if the roof is metal, the effect will be even stronger. Thermal insulation in this case takes on all the heat, preventing the temperature in the rooms from rising.

Also Read: The Advantages of Tiroof in Modern Roofing

Choosing material for insulation

Creating an external thermal insulation layer is a very significant and serious process. It is important to understand that not every traditional insulation is suitable for these purposes. In our case, it must have several properties:

• resistant to moisture – otherwise it will deteriorate after the first rain
• increased strength – weather conditions can be very harsh, external thermal insulation should not be afraid of strong winds and mechanical influences
• high thermal insulation characteristics – the material must retain heat well, otherwise it would be pointless to use it

Of course, it will be difficult for an inexperienced person to immediately select the appropriate material based on the stated parameters. Let’s look at the most popular offers.

Minvata

A traditional option, actively used in the post-Soviet space. Creates such material from all kinds of silicate waste, as well as mixtures of sedimentary rocks and metallurgical slag. Depending on the specific combination of raw materials, three classes of mineral wool are glass wool, slag wool, and stone wool.

If the house is of entirely of wooden, it is preferable to choose glass wool, since it does not burn at all. It is environmentally friendly, durable, and retains heat well. Slag wool is suitable exclusively for thermal insulation of non-residential premises since it contains many toxic elements.

The advantages of the material are as follows:

• excellent thermal insulation performance;
• good breathability;
• Long service life – some modifications can last up to 50 years.

The main disadvantage of mineral wool is its weakness to moisture. Mineral wool is cheap, so the overall finishing costs will not hit the budget too much.

Styrofoam

Classic material with a cellular structure. The beauty of polystyrene foam is that inside these cells there is an inert gas, which gives the product high insulating properties.

Strengths of foam:

• high noise and heat insulation
• lightweight
• environmental friendliness – the material contains synthetic components (harmless to humans) that prevent the spread of dangerous microorganisms
• Long service life – the material will last at least 50 years
• protection from moisture – foam plastic withstands contact with a humid environment.

Disadvantages include poor vapor permeability, sensitivity to fire, and lack of protection against rodents.

Penoplex

In its properties and structure it is very similar to polystyrene foam, the only difference is a thinner layer, which allows you to reduce the distance between the cells and add strength. In terms of weight, penoplex is much heavier than ordinary polystyrene foam, but in other respects they are similar. Depending on the insulation method, there are several classifications of penoplex separately for each category of structure: roof, walls, and foundation.

Strengths and weaknesses are equivalent to the previous point.

Ecowool

Here, use natural cellulose as the main resource, diluting it with boric acid. The prefix “eco” is use here for a reason – due to its composition, the material is not susceptible to mold, or rotting and does not allow the appearance of rodents. Moreover, the latter a priori cannot start in eco wool; such an environment is unfavorable for them.

Among other things, it is worth highlighting a few more advantages of eco-wool:

• perfect sound insulation – it will always be quiet and calm inside
• good vapor permeability – comparable to natural wood
• resistance to contact with moisture
• fire resistance
• record service life – up to 70 years.

The material has no obvious shortcomings. The only thing is that applying eco wool requires the use of special equipment, which will increase the overall finishing costs.

Polyurethane foam

The material uses a two-component mastic (less often a one-component one), synthetic resins, and a hardener. Applied it in a thin layer to the surface, and after hardening it increases in size many times over.

Advantages of polyurethane foam:

• the best thermal insulation performance among all presented materials
• resistance to moisture
• environmental friendliness – the material does not emit toxins, and rodents cannot live in it
• perfect sound insulation.

The disadvantages are the same as in the case of eco wool – installation is possible only with special equipment.