The Canadian Commission on Building and Fire Codes (CCBFC) is holding this review to seek your comments on a new objective, new functional statements, and proposed technical changes for the revised National Energy Code for Buildings (NECB), scheduled for publication in 2011. The NECB 2011 will offer intent and application statements, as well as objectives and functional statements, for all technical requirements. Application of the NECB 2011 will provide a significant improvement in energy efficiency over previous requirements. The NECB 2011 will apply to all buildings described in Article 1.3.3.2. of Division A of the National Building Code of Canada 2010 (NBC). Energy efficiency requirements for NBC Part 9, Housing and Small Buildings, are currently being developed and are expected to be released as interim changes to the NBC in 2012.

To ensure continuous development and maintenance of the NECB, the CCBFC has established the Standing Committee on Energy Efficiency in Buildings (SCEEB). More details concerning the terms of reference of this committee and its activities can be found at Standing Committee on Energy Efficiency in Buildings.

Your views are important! The purpose of this public review is to give you an opportunity to participate in shaping the NECB into an objective-based code, the same format now used for Canada’s other national model construction codes, and to provide your reactions to the proposed technical modifications.

To allow for the addition of new objectives to the national codes, the CCBFC, in conjunction with the Provincial/ Territorial Policy Advisory Committee on Codes (PTPACC), first developed a protocol that outlined the steps required for considering and establishing a new objective to ensure that the result was responsive to provincial/territorial needs and transparent to all stakeholders. This protocol was approved by the CCBFC in February 2009. Using the protocol, the CCBFC determined that regulations were an effective tool to support the policy direction of increased energy efficiency for buildings. It was concluded that other tools, such as education, incentives and labeling programs, are essential to the success of achieving the overall policy goal of energy efficiency.

See:

• Policy Case for Regulating Energy Efficiency in Buildings (PDF)
• Policy Case for Regulating Energy Efficiency in Housing (PDF).

A proposed new objective related to energy was then developed in winter 2010 by a joint task group of the CCBFC and PTPACC following a bottom-up analysis of the 1997 Model National Energy Code for Buildings (MNECB). The framework proposed by the task group was discussed and agreement was reached by the CCBFC on the establishment of one principal objective “Environment” that incorporated a secondary objective “Resources” and a subsidiary objective addressing “Excessive Use of Energy.” All NECB 2011 requirements are being attributed to this subsidiary objective.

This broad objective structure and hierarchy provides the flexible framework necessary for the provinces and territories to adapt the NECB 2011 to meet their specific needs. As the NECB 2011 was written to address only the efficient use of energy by the building, some provinces and territories may need to address other issues such as greenhouse gases and alternative energy sources. For example, an objective of limiting excessive emissions of greenhouse gases, with corresponding functional statements and requirements, could easily be added by a province or territory under the same principal objective, “Environment”, by adding a new secondary objective that addresses changes to the earth’s atmosphere. The CCBFC believes that this flexible framework in the NECB 2011 increases the potential for the harmonization of national, provincial and territorial codes.

Functional statements supporting the new objective were developed by a working group of the CCBFC/PTPACC joint task group. They were approved by the CCBFC at its February 2010 meeting and were used in drafting the technical requirements for the NECB 2011. Supplementary information, such as intent and application statements, will be developed at a later date and will be provided free of charge following the publication of the NECB 2011.

A guiding document will be developed in fall 2010 to explain how the adopting provincial and territorial authorities could modify the NECB 2011 to suit their own policy goals, objectives or technical needs. Background material will include information on how the proposed requirements may affect, and be linked to, other societal goals.

Major issues that steered the development of the technical requirements are outlined below.

At its July 2008 meeting, the Council of the Federation, which is comprised of Canada’s 13 Premiers, issued a statement requesting an improvement of 25% over the levels set by the MNECB 1997. The CCBFC chose this direction as the working target for the technical changes made to the NECB 2011, although other elements, such as technical viability, enforcement and cost/benefit analysis, were also taken into account. Provisions for the NECB 2011 were evaluated by a consultant and are currently showing a 27% improvement, in general, in energy efficiency over the MNECB 1997. This improvement was based on a sample of selected types and characteristics of buildings and was established as a weighted mean based on population that took into consideration the distribution of the archetypal buildings.

The NECB 2011 offers three methods of compliance, which is the same approach that was used for the MNECB 1997. Prescriptive requirements are out in Parts of Division B of the code that address building envelope, lighting, electrical power, heating, ventilating and air-conditioning systems, and service water heating. As an alternative to complying with the prescriptive path, a designer can use simple trade-offs that apply within each Part, or a performance compliance path that uses modeling of the whole building to achieve the same energy performance levels as the prescriptive path.

The rules for modeling are set out in Part 8 of Division B of the NECB 2011 and the general modeling approach remains unchanged from the MNECB 1997: a practitioner models the building as proposed, remodels it as if it had been built in accordance with the prescriptive requirements, and then compares the two results. If the performance level of a proposed solution meets the minimum acceptable performance level represented by the prescriptive solution in the Division B requirements, then the solution is acceptable.

The approach taken by the NECB 2011 is not to differentiate based on assembly construction but to address the energy used by the building regardless of the construction materials used. The consequence of this is that the market will drive the design, taking into account the energy efficiency provisions set by the Code. This approach differs from the one taken in the MNECB 1997, where relaxations in the requirements were allowed for construction materials that were difficult to make energy efficient. As the MNECB 1997 approach resulted in inconsistent performance levels and was difficult to justify, the CCBFC chose, in the NECB 2011, to address the energy used by the building, with no exemption within the prescriptive requirements for any assembly construction.

Although certain industry areas will have more difficulty in meeting the prescribed performance levels than others with respect to building envelope assemblies, the NECB 2011 allows an increase or reduction in insulation levels as an option for any type of construction when a designer chooses to follow the trade-off or performance compliance paths. Warehouses, for example, could reduce their required insulation levels by trading off their semi-heated nature, or their use of few windows.

All technical changes to the National Model Codes must contain supporting information that includes the cost implications of the proposed change. The cost, typically referred to as the incremental capital cost of construction, is the differential between the costs of construction based on the revised requirements and those based on the current requirements. A similar analysis is performed for the benefit side of the equation, where applicable.

Due to the minimal adoption of the MNECB 1997, as well as the time lag between the MNECB 1997 and the new provisions of the NECB 2011, the level set by the MNECB 1997 is not being used. Instead, current construction practices are being used as the “baseline” construction for the purpose of estimating the costs and benefits of the proposed changes.

After considering various costing options for technical requirements for energy, it was determined that two primary data are used by all methods, namely cost of construction and energy savings. Thus, supporting information related to cost implications are in the form of incremental capital cost of construction and incremental annual energy savings. The incremental annual energy savings were calculated using a population weighted and blended gas and electrical commercial rate (PDF) . The population weighted electricity commercial rate was used instead of the above rate for proposed changes related to lighting and electrical power applications.

The justification for differentiating requirements based on energy source is typically based on:

• costs of the energy source, which results in a document that intrinsically codifies both energy and economics
• a political decision to address greenhouse gas emissions, carbon footprint, supply and demand of energy sources and other such high profile issues, where the characteristics of the production of the different energy sources are deemed to result in different impacts on this high level goal in that particular jurisdiction.

However, a complicating factor in establishing requirements based on the costs of the different energy sources is that one energy source may be more costly than another in a province or territory. The relative cost of energy sources also varies over time. In addition, as the authority to regulate energy rests at the provincial and territorial level, one political direction can be established within a single jurisdiction, but establishing a similar direction for a national code is difficult because the characteristics of the production of the different energy sources may differ from jurisdiction to jurisdiction.

The NECB 2011 therefore does not differentiate requirements based on energy source. It addresses energy used by the building irrespective of the energy source, and does not have different performance levels for construction based on each energy source. Guidelines will be developed for the jurisdictions to use in tailoring the NECB 2011 to suit their specific policy directions, including weighting of fuel sources and the use of renewable/alternative energy sources.

Alternate energy sources in this context include renewable energy, waste energy, site-generated energy and energy derived from the commercial or industrial use of the building (process energy). There are inherent difficulties with assigning a definition to these terms that might be acceptable to all jurisdictions, and they are therefore not addressed in the NECB 2011 prescriptive and trade-off paths. By remaining silent on these topics for compliance paths in the acceptable solutions, the NECB 2011 allows jurisdictions to consider proposals using them. This facilitates flexibility and innovation in the energy performance design of a building using these alternative sources.

Farm buildings remain excluded from the scope of the NECB 2011, as they were from the MNECB 1997. This may be revisited for the subsequent edition.

The underlying principle of the NECB 2011 is to address energy used by the building, ideally resulting in an energy intensity target. Different building occupancy types have varying architectural characteristics, such as fenestration to wall ratios, and different operational profiles. Advances in construction materials and methods have decreased the barriers to achieving a set energy performance level for buildings irrespective of these architectural and operational parameters. The NECB 2011, therefore, does not set different levels of thermal performance for building envelope based on occupancy. Some types of buildings having unique characteristics may be affected; for example, hospitals, which expend a lot of energy ventilating air, will need to use heat recovery systems in order to meet the energy targets.

Unconditioned spaces (i.e. spaces that are not heated or air conditioned) are included in the application of the NECB 2011, with few general exceptions (e.g. greenhouses). Specific trade-off provisions have been added in the building envelope Part of the NECB 2011 that deals with semi-heated spaces.

Air leakage has a significant impact on the energy performance of buildings and is one of the major sources of heat loss. The SCEEB will continue its work in this area to establish stricter requirements to limit unwanted air leakage of conditioned air from buildings in a subsequent publication.

Lighting of unoccupied interior spaces is an unnecessary use of energy. The NECB 2011 therefore requires the installation of automatic lighting controls for many applications.

Significant discussions were conducted involving fenestration to wall ratio, as it bears heavily on the energy performance of buildings because windows are significantly less energy efficient than opaque wall assemblies. An informal survey conducted by the SCEEB across the country determined that typical fenestration to wall ratios varied from about 40% in warmer climates to 20% or less in colder climates. The SCEEB’s subsequent proposal to set the maximum fenestration to wall ratio at 40% in the prescriptive building envelope requirements of the NECB 2011 was supported by the CCBFC. The requirement is expected to affect some buildings, such as all-glass condos in Toronto and Vancouver. However, the trade-off approach provides flexibility and, in the case of all-glass condos, adding more windows could be offset by increasing the insulation in opaque wall elements to ensure that the energy usage is maintained. A lower maximum fenestration to wall ratio has been set for colder regions of the country and further flexibility is provided through use of the performance compliance path.

Heat recovery equipment produces significant energy savings by capturing heat embodied in exhaust air that would otherwise be thrown away. The NECB 2011 therefore requires the installation of heat recovery equipment for most applications.

The federal Energy Efficiency Act (EEA) contains, among other things, minimum efficiency standards for HVAC and service water heating equipment. When compared with current industry practice, the minimum efficiencies set by the EEA were found to be below that of the typical equipment installed today. The SCEEB therefore set a minimum efficiency, in the prescriptive path, based on the industry's median level for much of HVAC and service water heating applications. Flexibility is provided in the trade-off path by allowing designers to use equipment down to the EEA levels, provided the overall system efficiency is equivalent to one resulting from the prescriptive path. The modeling approach has the same relaxation.

*Source: National Research Council Canada, 2010. Review of Canada's National Energy Code for Buildings 2011