The resistance of an insulating material to conductive heat flow is measured or evaluated in terms of thermal resistance or R-value – the higher the R-value, the greater the insulating efficiency. The R-value depends on the type of insulation, its thickness and density. The R-value of most insulation also depends on temperature, aging and moisture accumulation. When you calculate the R-value for a multi-tier installation, you add the R-values for each layer. To choose the best insulation for your home from the many types of insulation on the market, you need to know where you want or need to install the insulation and what R-value you want the installation to reach. Other considerations may include impacts on indoor air quality, life-cycle costs, recycled content, grey carbon, and ease of installation, especially if you want to do the installation yourself. Some insulation strategies require professional installation, while homeowners can easily manage others. R-values are used to determine the minimum insulation value of different parts of houses. Insulated ceilings prevent heat from escaping from the top of a building and can prevent damage from ice dams. This is less important in warmer areas, which have an R-value of 30 in zones 1-3 and a value of 38 in zones 4 and 5. Zones 6, 7 and 8 have a value requirement of 49. For more information on IECC requirements or to learn more about insulation, contact USI online to find a branch near you and get a free quote.

USI believes in excellence every step of the way, ensuring timely completion and quality of service, again and again. The amount of insulation or R-value you need depends on your climate, the type of heating and cooling system, and the part of the house you want to insulate. For more information, see our information on adding insulation to an existing home or insulating a new home. Also, keep in mind that airtightness and humidity control are important for energy efficiency, health, and home comfort. Soils have a required R-value of 13 in zones 1 to 3 and 19 in zone 4. From zone 4-Marine to zone 8, the requirements have the condition that the room is met at least if you cannot reach the R-value with the space provided. The requirements for the remaining areas are 30 for 4 sea zones to 6 and 38 for 7 and 8. Regulations created by the International Code for Energy Conservation (IECC) are designed to keep buildings as energy efficient as possible in terms of heating and cooling. Here`s an overview of the different insulation and window factors they take into account, as well as the requirements in the eight U.S. climate zones. Each county in the United States is sorted by these climates, which are divided into wet, dry, and sea. While it is possible to calculate an R-value for a particular radiation barrier or reflective insulation installation, the effectiveness of these systems lies in their ability to reduce heat gain by reflecting heat away from the living space.

The effectiveness of the heat resistance of an insulation material also depends on how the insulation is installed and where it is installed. For example, compressed insulation does not return the full nominal R-value. The total R-value of a wall or ceiling is slightly different from the R-value of the insulation itself, as heat flows more easily through bolts, beams, and other building materials, called thermal bridges. In addition, the insulation that fills the building`s cavities reduces airflow or leakage and saves energy. Installing more insulation in your home increases the R-value and resistance to heat flow. In general, an increased insulation thickness proportionally increases the R-value. However, if the thickness installed for bulk filling insulation increases, the settling density of the product increases due to the compression of the insulation under its own weight. Due to this compression, the R-value of bulk filling insulation does not change in proportion to the thickness. To determine how much insulation you need for your climate, contact a local insulation contractor.

Use the following map to determine your climate zone, and then use the tables below to estimate the required R-values. For more information on climate zones, see the International Code for Energy Conservation 2021. Unlike traditional insulation materials, radiation barriers are highly reflective materials that release radiant heat again instead of absorbing it, reducing the cooling load. Therefore, a radiation barrier has no inherent R-value. It is a wall made of something other than wood with insulation and drywall. Brick, stone, and concrete are common masonry walls, and the width of the material can increase the insulation value instead of relying solely on additional insulation. The R-values of these walls are lower than those of hollow timber frame walls because the wall materials have natural insulation values. Zones 1 and 2 have required values 3 and 4, zones 3 and 4 have required value 5. Marine zones 4 and 5 have a required value of 13.

Zone 6 requires an R-value of 15 and zones 7 and 8 require a value of 19. Soil serves as a very insulating material, so in many cases less insulation is needed in underground areas. The three structures have similar R-values within a region. No insulation is required for zones 1 and 2. Zone 3 requires an R-value of 5 in basements and crawl spaces, but nothing for signs. Zones 4 and 5 require an R-value of 10 for all three structures. Zones 6, 7 and 8 also have an R-value of 10 for slabs and crawl spaces and 15 for basements. *Note: In the table above, CI stands for “continuous insulation” which is placed on the outside of the wall assembly just inside the cladding. Insulation materials range from bulky fiber materials such as fiberglass, rock wool, cellulose and natural fibers to rigid foam boards and thin films.