Energy regulations have pushed construction materials manufacturers to prioritize eco-friendly options. These new materials offer a wide range of benefits such as reduced energy consumption, improved indoor comfort and enhanced durability.
They also provide cost savings by minimizing heating and cooling needs. These materials can be grouped into different categories depending on their ability to absorb, retain and release heat energy.
Materials with High Thermal Mass
A building with high thermal mass is able to absorb and store the sun’s heat, reducing the need for active heating and cooling systems. This is due to the material’s inherent properties, such as specific heat and density. Concrete, brick and stone are common examples of construction materials with high thermal mass.
These materials are designed to act like a battery, absorbing the sun’s heat during the day and releasing it at night. This is useful in hot, dry climates that experience large diurnal temperature variations between day and night. The heat from the materials is slowly released throughout the evening, keeping the indoor space warm and comfortable without overheating.
The type of stone, tile or brick used is a critical aspect in determining the overall thermal performance of the building, as each material has a different ability to absorb and re-radiate heat. The thermal lag is also important, as some materials take longer to absorb and release heat, while others take less time.
Using the right building materials is an essential part of passive design, and can help you meet energy efficiency and green certification requirements and reduce your heating and cooling costs. When used in combination with other passive design elements, such as the right orientation, insulation and appropriate glazing, high thermal mass can be a great way to passively heat your home and maintain comfortable temperatures all year round.
Materials with Low Thermal Mass
Thermal mass is the ability of a material to absorb and store heat. It is a key factor in reducing artificial energy demand and the need for air-conditioning. It reduces diurnal temperature variations and provides comfort to occupants. It is important to choose construction materials with high thermal mass such as concrete, brick, adobe walls or recycled rammed earth, and incorporate them strategically in the building.
The heat capacity of a material is determined by its specific heat and density. The higher the density and specific heat, the better the material is as a thermal mass. A material’s volumetric heat capacity is also a key consideration, since it is the total amount of heat that can be stored per unit volume.
A material’s thermal lag is the time it takes to release stored heat. It depends on the material’s heat capacity and is defined by its specific heat, density and volumetric heat capacity. Concrete, for example, has a high volumetric heat capacity but a low specific heat. Wood, on the other hand, has a low volumetric heat capacity and a high specific heat.
To maximize the effectiveness of thermal mass, it is best located within the core of a building where natural ventilation can effectively transfer heat to and from it. In addition, it is beneficial to situate the mass away from areas that are not exposed to much sunlight or are prone to overheating.
Materials with High U-Values
Although much of the focus in the construction industry is on energy efficiency, thermal performance must still be considered. One important aspect of this is the U-value of a building’s walls, floors, and roofs. This figure is calculated by measuring heat transfer through a material’s layers and determines the effectiveness of the insulation. A high U-value indicates a poor level of insulation and leads to higher heating costs.
Using materials with low U-values minimizes heat transfer, and results in lower energy bills and carbon emissions. In addition, some governments and utilities offer financial incentives and rebates for building projects that meet specific energy performance standards.
Achieving a low U-value requires careful consideration of the materials used and the way that they are assembled. The thickness of the material impacts its U-value, as does its thermal conductivity and air infiltration. It is important to know which insulation materials have the best U-values and how to install them correctly.
Online U-value calculators and some more advanced modeling software are available to calculate the U-value of a given part of a construction. Alternatively, it’s worth knowing how to do the calculations yourself. For example, a standard timber frame wall with mineral wool as an inner skin would have a U-value of 0.19W/m2K. However, if the same wall was constructed using SIPs with expanded polystyrene as an inner skin and an outer layer of OSB then the U-value would be 0.27W/m2K.
Materials with Low Insulation Values
Insulation materials come in many different forms, each with unique characteristics that affect their performance. One major factor in insulation performance is its R-value, which is based on the material’s inherent ability to resist heat flow.
Different types of insulation materials offer different R-values based on their thickness. For example, fiberglass batts typically have an R-value of around R-3 per inch of thickness, while blown cellulose has a higher R-value at approximately R-6 per inch of thickness.
The R-value of insulation can also be affected by other factors. For example, if there are gaps or voids in the insulation, it can lose some of its effectiveness. Additionally, if the insulation is installed improperly or it is exposed to moisture or high temperatures, its R-value can decrease over time.
Choosing the right insulation is an important part of making your building more energy efficient, and it can help reduce heating costs significantly. However, it is important to remember that the initial cost of installing insulation can be expensive, and it may take a while for your energy savings to pay for the upfront investment.
Also, there is a point of diminishing returns where adding more insulation does not provide significant energy efficiency benefits. Therefore, it is essential to consider the material type, R-value, and other factors when choosing insulation for your building.