Around the world, energy codes are recognized as one of the most cost-effective tools for achieving energy efficiency in buildings. Energy codes result from deep consultation among governments, industry and professional experts.
How Canada got its energy code
A consortium of provinces, utilities, industry stakeholders, the National Research Council of Canada (NRC) and Natural Resources Canada developed the Model National Energy Code for Buildings (MNECB) in 1997. It was Canada’s first national standard for building energy performance and it influenced the way buildings were designed in Canada for more than 15 years.
The code evolves
In 2011, the MNECB was updated and renamed the National Energy Code for Buildings (NECB) for consistency with the other model national construction codes (NBC, NPC, NFC) including an average 25 percent performance improvement over its predecessor. The NECB outlines the minimum energy efficiency levels for all new buildings and offers more flexibility for achieving code compliance.
The current National Energy Code of Canada for Buildings (NECB 2015)
The NECB was last updated on December 18, 2015. NECB 2015 contains more than 90 new changes that will further help to ensure a high level of energy efficiency in new Canadian buildings.
Some examples of these changes include:
- new thermal requirements for semi-heated buildings
- updated maximum allowable lighting power densities, which are harmonized with those of ASHRAE 90.1-2013
- new prescriptive requirements for hydronic pump systems and heat rejection equipment
- demand control ventilation for parking garages
Build to code and save on energy
Building to meet the NECB will help save on energy bills, reduce peak energy demand, and improve the quality and comfort of the building's indoor environment.
Sustainable, energy-efficient buildings built to the code can also help to
- improve worker productivity by approximately 5 percent
- deliver a rental premium of 3 to 5 percent
- increase sales value between 8 and 26 percent
Building to code is the most cost-effective option
The most cost-effective time to incorporate energy efficiency measures into a building is during the initial design and construction phase. It is much more expensive to retrofit later. This is particularly true for the building envelope.
The NECB focuses on five key building elements typically considered during design:
- Building envelope – Includes walls, windows, doors and roofing, and addresses air infiltration rates and thermal transmission.
- Lighting – Measures such as reducing lighting power densities, using lighting controls and making effective use of available daylight are all considered here.
- Heating, ventilating and air conditioning systems – Includes heat recovery ventilation, pipe and duct insulation, and building automation and control systems to optimize equipment operation.
- Service water heating – Considers all the ways hot water is used in a building and includes requirements to limit water flow rates and maximize waste-water heat recovery, and sets minimum performance standards for service water heating equipment.
- Electrical power systems and motors – Establishes requirements for monitoring energy use of electrical distribution systems, sets limits on the size of conductors so as to minimize voltage drop, and establishes standards to govern the selection of transformers and electrical motors.
How to show you are in compliance
Prior to issuing a building permit, municipal code officials will generally require evidence that the design is code compliant. The NECB offers three compliance paths: prescriptive, trade-off and performance.
This compliance path involves following the prescriptive requirements of each section of the code. Your local building permit office may require you to complete and submit a checklist as part of your building permit application.
This compliance path provides some flexibility by allowing certain elements within the same part of the code to be traded. For example, if your design calls for more window area than prescribed by limits in the code, you may be able to compensate by improving the insulation in the walls. NRCan offers downloadable trade-off path calculation tools to help you with this compliance path.
This approach offers the most design flexibility. You must show that the proposed design will not consume more energy than an equivalent building built to the prescriptive requirements of the code. For this compliance path, you must use a building-energy simulation tool, such as CAN-QUEST, a specialized software application available free from NRCan.
Using CAN-QUEST to show performance path compliance
Based on data from design drawings and specifications, CAN-QUEST will simulate the building design and generate a report that shows the annual energy use of the proposed building as well as that of a similar building that strictly meets the prescriptive code requirements. Once the report has been certified by a design professional, it may be used as evidence of compliance with the code.