Investing in proper insulation for your home is a great decision that provides both comfort and savings in the long run. However, before you embark on upgrading your home's insulation, it's essential to understand the basics. Recognizing the importance of insulation material and the right strategy can make all the difference. But what exactly does thermal insulation mean?
Thermal insulation consists of reduce heat transfer between the interior and exterior of a home by using specific materials that block such transfer. In this article we will talk about the best thermal insulators that you can use in your home and what their most notable features are.
Importance of thermal insulation
Thermal insulation is the process of preventing the transfer of thermal energy, that is, reducing the flow of heat between two media that are at different temperatures. Materials that hinder this transfer are called thermal insulators. They protect our homes from external heat and cold, ensuring that the interior temperature is more comfortable.
Insulation works because contains small air pockets which slow down the flow of heat. During the winter, an uninsulated house loses heat, which means that more heating costs are needed to maintain the interior temperature. In the summer, the opposite occurs: heat enters easily, increasing the need for air conditioning. With good insulation, both heat loss in winter and heat gain in summer are avoided.
There are many materials on the market, both natural and artificial, that serve to provide thermal insulation. Natural materials include wood, hemp or cork. On the other hand, artificial materials, such as polystyrene or polyurethane foam, have been explicitly designed to offer greater insulating capacity.
What type of thermal insulation is most effective?
To determine the effectiveness of a thermal insulator, it is crucial to observe its Thermal conductivity, measured in W/K·me, generally indicated by the Greek letter lambda (λ). This value expresses the quantity of thermal energy that passes through the material. The lower the thermal conductivity value, the better the insulating capacity of the material.
A material is considered an insulator if its thermal conductivity is equal to or less than 0,05 W/K m. Below is a list of the thermal conductivity factors. main insulating materials used in construction and their ability to keep your home at an ideal temperature.
The best thermal insulators for your house
Below, we will analyze some of the best thermal insulation options for your home, taking into account their characteristics and efficiency:
- Polyurethane foam: This plastic material is known for its excellent insulating capacity, with a thermal conductivity of between 0,025 and 0,035 W/K m. Polyurethane foam is applied by spraying, forming a solid layer after expansion. It insulates well, but its main drawback is the difficulty in controlling the thickness uniformly when applied.
- Extruded polystyrene (XPS): Another of the most effective materials, extruded polystyrene has a thermal conductivity ranging from 0,025 to 0,039 W/K m. It is highly resistant to moisture absorption and withstands mechanical loads well, making it a common choice for walls, ceilings and floors.
- Expanded polystyrene (EPS): Similar to XPS, EPS offers slightly higher thermal conductivity, ranging from 0,029 to 0,046 W/K m. It is also derived from petroleum, but is more affordable and more commonly used in construction. However, it is more absorbent than XPS, so it is not suitable for all applications where moisture is present.
- Mineral wool: This group includes both glass wool and rock wool, both used in rigid or semi-rigid panels. Its thermal conductivity ranges from 0,031 to 0,050 W/K m. In addition to being a good thermal insulator, mineral wool is also effective for acoustic protection and is highly resistant to fire.
- Cellulose: Made from recycled paper and treated with fire-retardant products, cellulose is an ecological alternative with a thermal conductivity of around 0,04 W/K m. It is usually applied by blowing into cavities and is ideal for hard-to-reach spaces.
- Wood fiber: This naturally derived material has a conductivity of 0,038 W/K·m and is suitable for those looking for an eco-friendly option. Its biggest advantage is its sustainability, although it does not have the same mechanical properties as synthetic materials.
- Expanded cork: Cork, a natural material, has been used as an insulator for centuries. Its thermal conductivity varies between 0,037 and 0,040 W/K m. In addition to being a good thermal insulator, it offers excellent acoustic performance and is highly resistant to moisture and fire.
- Cellular glass: Another highly effective insulator is cellular glass, which has exceptional properties in terms of permeability and resistance to decay. Its thermal conductivity is 0,035 to 0,040 W/K m, and although it is more expensive than other insulators, it is used in applications where performance is key.
Aspects to take into account when choosing a thermal insulator
When choosing the best insulation material for your home, there are several factors to take into account:
- Thermal conductivity: As we have seen, the lower the thermal conductivity of the material, the more effective it will be at preventing heat flow. For cold climates, look for lower values.
- Fire resistance: Some materials, such as glass and mineral wool, are highly fire-resistant. This can be crucial in environments where the risk of fire is high.
- Permeability: In humid areas, it is best to opt for an insulating material that offers resistance to water vapour and condensation. Materials such as XPS and cellular glass are ideal in these cases.
- Environmental impact: The use of recyclable and sustainable materials such as cork or cellulose can make a difference in ecological constructions.
- Acoustic isolation: In addition to thermal insulation, some materials, such as mineral wool and cork, offer additional advantages in terms of noise reduction.
Key areas to insulate in your home
While it's important to insulate your entire home, some areas are especially critical to prevent heat loss or cold entry. Make sure to pay attention to the following areas:
- Facades: Because they are exposed to the elements, facades require adequate insulation. Poor insulation on exterior walls can result in significant heat loss.
- Roofs and coverings: Around 30-35% of the heat in a home is lost through the roof. Good insulation in this area is essential to improve energy efficiency.
- Windows and doors: These are critical points where a lot of heat can be lost. Make sure that windows are double-glazed and use insulating seals on doors.
- Floors: Especially on ground floors or basements, floors can be sources of heat loss. Insulating floors with EPS or XPS can help reduce energy loss.
By considering all of these recommendations, it is possible to significantly improve the thermal efficiency of your home. By choosing the right material based on your needs and climate, you can make noticeable improvements to your home's comfort, all while saving hugely on heating and air conditioning.