The Insulation Building Code 2021

The insulation building code is part of a legal framework adapted from New York’s Building Code.

Serving as a regulator of the construction and energy efficiency standards it was formed to avoid unstable construction practices and unsafe materials. The insulation building code 2021 forecasts the best insulation R-Value, layer thickness, type of materials being used, installation model, and many more factors influencing insulation systems. Energy efficiency has been an objective of the insulation building code since 2006. Setting up standards as requirements have lowered the average home energy consumption by 50% in less than 10 years. The main goal is to guarantee the safety and comfort of both builders and homeowners.

Insulation Building Code 2021 Requirements

  1. I) R-Value

R-Value defines how well a barrier such as an insulation layer resists air leakage. It measures the capability of an insulation system to keep a building compact and block heat flow. A high insulation R-Value is not easy to be achieved. It requires the proper materials to be installed in a proper manner. Different insulation methods offer different R-Value. To increase your home insulation efficiency an appropriate layer thickness is needed too.

Minimum R-Value that meets the insulation building code 2021 demands is very variable considering the part of the house you are insulating and the area where you live. Exterior walls, for example, are recommended to have an Insulation R-Value of at least R-40, while ceilings and attic spaces will need a higher R-Value which with new recommendations, goes up to R-60.

*The below table shows the minimum R-Value requirements for different areas.

                                                                             Picture (R-Value-map)

Walls R-30 to
R-33 to R-40   R-35 to R-45    R-45
Basement walls R-30 to
R-33 to R-40   R-35 to R-45    R-45
Roof or Ceiling R-45 to
R-55 to R-60   R-55 to R-60    R-60
Floor (over
unheated spaces)
R-35 to
R-40 to R-45   R-50 to R-55    R-55
  1. II) Installation model

Each section of a house that separates the outside from the inside and vice versa must have:

  • A thermal barrier
  • An air barrier
  • A vapour retarder

These barriers make what is called the Insulation system. According to the insulation building code 2021, the proper installation is key for an insulation system to work efficiently and last for as many years as possible. The insulation system must be in contact with an air barrier to prevent the airflow through the material. This is why every insulation crew must check for any gaps or cracks in the wall perimeter prior to the insulation process start. In case the insulation is exposed to water it is recommended to be at least 2” above the crawl space floor. If the insulation material is vulnerable to weather conditions, it would be better to be protected by a 12mm thick cement parging or a 6mm preservative plywood.

III) Attic insulation

If you have already insulated your home but not your attic, then you are making a small but significant mistake. Hot air is lighter, which makes it go up to the attic and penetrate out of the house. The heating system will have to reheat the cold air more than usual, causing a shock on the energy bills. Attic insulation not only prevents the airflow but also makes it easier to maintain a constant temperature around the house.

With new regulations from the Insulation building code 2021, the attic insulation R-Value has changed from R-50 to R-60. To increase the attic insulation R-Value a new layer needs to be added over the existing insulation. Batt, cellulose, spray foam, or even a combination of these methods would be suitable for insulation to achieve the required R-Value.

IIII) Continuous insulation

Another important factor that determines the good function of your home insulation is continuous insulation. The main rule of continuous insulation is a monolithic insulation system that can eliminate thermal bridging through materials that are not treated with an overlapping insulation layer. The insulation building code has targeted thermal bridging as an insulation practice that can be improved by applying continuous insulation. It can be achieved if you install rigid board stock all around the perimeter of the area that will be insulated to block air pockets and gaps around the perimeter. The main goal is that home insulation serves as a better monolithic system that reduces heat loss.

Updates and changes to the insulation building code 2021

Energy efficiency standards have changed a lot since the New York building code first got introduced to the public in 1975. The government often intends to update the insulation building code to adapt to new industry practices and requirements. The energy efficiency requirements attempt to lower the demand for energy from society, causing lower bills and a reduction of greenhouse gas emissions. The latest changes expected to be approved in 2021 give attention to existing and new insulation systems for homes and large buildings.

Proposals include:

New energy efficiency demands for houses:

  • Continuous insulation demands in all walls regardless of the chosen compliance path.
  • Air leakage testing without concern for results.
  • Improved wall insulation for new buildings.
  • Requirements for Under-slab insulation.
  • Requirements for energy efficient sliding doors and triple-pane windows. (U-Value 1.4)
  • Extra limitations to complete elimination of the building envelope trade-offs.

New energy efficiency demands for large buildings:

  • Insulation removal exceptions to reduce thermal bridging impact.
  • Mandatory testing to the building air barrier without concern for results.
  • Expansion of energy recovery requirements for apartment buildings.

With new rules expected to be approved soon, homeowners are now one step closer to more energy efficiency standards and practices. Thanks to the insulation building code, an energy-efficient feature, such insulation systems, can now do more than they were used to do in the past. At the end of the month, this is translated to fewer expenses from homeowners for energy bills, less use of energy for the same tasks, less pollution to the environment, and more comfortable living spaces.