Thermal insulation materials to improve energy efficiency

Thermal insulation is one of the keys for a home or workplace to achieve the highest degree of energy efficiency. Both in summer and winter, achieving good airtightness in buildings allows us to avoid high energy consumption in air conditioning, which leads to higher bills. But for this, it is necessary to have thermal insulation materials that guarantee us the greatest comfort.

Why is it necessary to achieve airtightness in buildings? Basically, because we can keep the cold and heat out of the home in winter and summer, efficiently tempering our rooms. Historically, old buildings breathed, which is how the phenomenon of air filtering through windows and doors is described, in addition to through the walls themselves. This made it so that in summer the heat came in and in winter the cold.

The solution given decades ago was to go out for a walk in the summer to avoid the heat of home and to use blankets in winter. But through insulation of homes we can avoid these cumbersome phenomena, as well as not having to make excessive use of traditional air conditioning systems. And to gain comfort, the use of air conditioning and heating devices was chosen, which require a huge energy effort.

While it is necessary to use mechanical ventilation systems in homes with good airtightness - as it is the best way to guarantee airflow - we also save a lot of energy and bet on energy efficiency. And for this, it is necessary to use the correct thermal insulation materials in the construction or rehabilitation of buildings.

As an example of the importance of airtightness in buildings, we can remember that the Passivhaus certification seal for passive houses - which is a reference alongside BREEAM - considers that thermal insulation is one of the five main conditions to guarantee energy efficiency and avoid consumption in a building.

What insulating materials do we find in the market?

• Mineral wool insulators. It is the most common insulating material. It is made from volcanic rock and has a slightly rigid panel form. They can be made of rock wool or fiberglass, and consist of insulators with intertwined filaments of stony materials. In addition to significantly improving the airtightness of the rooms, they also protect against noise, making them good acoustic insulators. They can also offer fire protection.
• Synthetic insulators. These are insulating materials such as plastic or polymers that come from petroleum, as they are all considered synthetic. They have great thermal efficiency, and among them, polystyrenes - very commonly used - polyurethane - which can get wet and is more absorbent - or reflective rolls stand out. The latter have variable thickness.
• Natural insulators. They are considered the ecological option, which is why they are becoming more widespread. They are also the option that bioclimatic houses would require. The most common is cork, as in addition to its insulating properties, it is also recyclable and renewable. But we also find cellulose, linen, sheep's wool, cotton, and coconut fiber. Some of these can be used like blankets within the walls.

Our choice of thermal insulation materials should be made based on our needs and the specific project, but there are plenty of options in the market to ensure that its use is widespread.

The importance of using thermal insulation materials

The Passivhaus certification seal is a great example to explain the importance of airtightness to guarantee energy efficiency. The German group that created one of the most recognized standards for passive houses - to certify those residences that do not require artificial air conditioning. Passivhaus considers that thermal insulation is key for this:

By using an appropriate thickness of thermal insulation, passive houses suffer very low heat losses with heating needs being almost zero. To achieve this, it is essential that the design and execution of the exterior walls, roof, and floor are carried out by analyzing all the construction details.

Likewise, the BREEAM energy efficiency seal also considers that thermal insulation is essential to achieve a good score in obtaining its certificates.

There are sufficient thermal insulation materials to carry out sustainable projects that do not force large expenses in air conditioning. Likewise, this airtightness is also one of the keys for Nearly Zero Energy Buildings, which will be mandatory starting in 2020 in Spain for all new construction, whether public or private.