Archived – Public Review on Proposed Changes to the National Model Codes – 2003

Noncombustible Materials - Sentences 3.1.5.1.(1) and (2)

It is proposed to amend NBC Article 3.1.5.1. to allow the acceptance of materials of limited combustibility based on specific criteria. The change is proposed on the basis that the noncombustibility test excludes materials that pose a low risk but that have other desirable properties. This change would allow various products, such as washable interior finishes, to be used in buildings in which they are currently not permitted.

Firewalls - Sentences 3.1.10.2.(3) and (4)

It is proposed that NBC Article 3.1.10.2., which stipulates that masonry or concrete be used for the construction of 2-hour firewalls, be changed from a prescriptive requirement to a more performance-based requirement. This change is proposed to accommodate various provincial, territorial and builder requests and to facilitate construction under adverse climatic conditions. It would allow design alternatives to be proposed while continuing to spell out a comprehensive set of performance requirements.

Mezzanines - Article 3.2.1.1., Sentence 3.2.1.6.(1), Articles 3.2.8.2. and 3.4.2.2.

A number of changes are proposed to address the whole concept of mezzanines. The changes address such issues as calculation of building area, fire-resistance rating and exit travel distance, while aiming to clarify the application.

It is anticipated that these changes would facilitate plan review, design and end-user compliance thus reducing the number of technical inquiries that are submitted.

Voice Communications - Article 3.2.4.23.

It is proposed to add this Article which would require a voice communication system in certain mercantile occupancies, specifically the "Big Box Stores" (refer to Article 3.2.4.23.). This new provision addresses life safety concerns raised by a National Fire Code standing committee as a result of several human behaviour studies and past fire incidences in similar stores.

Barrier-Free Washrooms - Article 3.8.3.12.

It is proposed that both terminology and function change from "special washroom" to "universal toilet room". This terminology would more adequately express the function of these rooms and allow them to be multi-user and multi-functional.

This change is aimed at facilitating compliance for owners and regulators while maintaining the established barrier-free washroom requirements.

Plenum Cables - Definition of communication cable in Article 1.1.3.2., Sentences 3.1.4.3.(1) & (2), Article 3.1.4.4., Sentences 3.1.5.17.(1) and (2), Sentences 3.1.5.19.(1) and (2), Sentence 3.6.4.3.(1)

It is proposed that the rating of communication cables and totally enclosed nonmetallic raceways located in plenums of Part 3 buildings be increased from FT4 to FT6. The change would further limit the flammability and impose control on the smoke generation potential of communication cables and raceways located in ceiling spaces used for air handling.

Special Changes

The Canadian Commission on Building and Fire Codes has authorized the issuing of two special code changes without submitting them for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Foamed Plastic Insulated Panels - Sentence 3.1.5.11.(7)

This change allows the use of factory-produced insulated panels in the construction of cold storage buildings. This change will eliminate the burden on industry and designers to continue to request and support the acceptance of these panels. A ULC Other Recognized Document (ORD) will also be referenced to assist the authority having jurisdiction in the acceptance of products.

Special Change: Nonmetallic Raceways - Sentence 3.1.5.19.(1)

This change allows larger sized nonmetallic conduit within a fire compartment. The ability to use nonconductive and relatively corrosion-resistant raceways in industrial buildings and in service spaces will have a safety benefit for persons working in proximity to the raceways. In some cases, there will be a cost benefit to permitting a wider choice of code-complying materials.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NBC, stakeholders are strongly encouraged to review and comment on the entire package of changes.

The proposed changes to the structural design requirements of the NBC have resulted in a rewrite of Part 4 which was performed by two separate groups of experts: the Task Group on Snow and Wind Loads and the Canadian National Committee on Earthquake Engineering (CANCEE). CANCEE revised the earthquake design Subsection of Part 4 and the Task Group modified the remainder. The alterations were presented to and approved by the Standing Committee on Structural Design.

Use and Occupancy, Snow and Wind Loads - Subsections 4.1.5., 4.1.6, 4.1.7.

The Task Group studied the design philosophies employed by other countries and code-writing agencies, reviewed the performance of Canadian buildings subject to climatic loads, and looked at inconsistencies in, and the organization of, Part 4 of the NBC. As a result, the following principal revisions were made:

• the adoption of the companion load format for load combinations
• a redefinition of the specified loads to be compatible with the companion load format, which includes the separation of the snow load from the live load
• the use of importance factors and importance categories to modify the design loads for various use and occupancies
• the adoption of a 50-year return as a basis for snow, ice, rain and wind loads
• the removal of working stress design, and
• a reorganization of Part 4 and the Commentaries to improve readability.

Earthquake Engineering - Subsection 4.1.8.

CANCEE undertook the review of all the requirements in NBC 1995 Subsection 4.1.9., Live Loads Due to Earthquakes, and sought to incorporate as much recent knowledge, information and experience as possible in the next version of the NBC. The key updates include the following:

• the use of the spectral response acceleration values in the climatic tables
• the requirement to separate other elements of the structure from the Seismic Force Resisting System (SFRS), or to include the other elements as part of the SFRS
• a definition of irregularities with some restrictions for certain types of buildings and certain earthquake zones
• the establishment of dynamic analysis as the default method, with the use of the equivalent static force procedure allowed if certain criteria are met
• the replacement of the force modification factor, R, with a ductility-related force modification factor, Rd, and an overstrength-related force modification factor, Ro
• the addition of provisions for rocking footings, and
• the revision of provisions or parts thereof to reflect the National Earthquake Hazards Reduction Program (NEHRP) provisions.

Special Change

The Canadian Commission on Building and Fire Codes has authorized the issuing of one special code change without submitting it for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Snow Loads on Arched Roof Structures - Sentence 4.1.6.3.(2), Figures H-2(a) & H-2(b)

The Standing Committee on Structural Design initiated a special change to the snow loads on arched roof structures based upon a report by Rowan Williams Davies & Irwin Inc. As a result, the partial snow load provisions of Sentence 4.1.7.2.(2) in the NBC 1995 will extend to all arched roof structures in Sentence 4.1.6.3.(2) of the NBC 2005 [see 4.1.6.3.(2)], and the trigger for the unbalanced snow load condition described in Figures H-2(a) and H-2(b) of the Structural Commentaries will be reduced for arched roofs with a rise-to-span ratio of 1/20.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NBC, stakeholders are strongly encouraged to review and comment on the entire package of changes.

Structural Requirements for Environmental Separators and Assemblies Exposed to the Exterior - Article 5.1.4.1., Subsection 5.2.2.

Recognizing that Part 4 does not identify all the elements of environmental separators and assemblies exposed to the exterior to which structural design must apply, a series of changes is proposed as an initial step to address this issue within Part 5. The proposed changes recognize, for example, that air barrier systems and roofing are not the only elements that must be designed to resist air pressure loads. The proposed changes also recognize that some building elements need not be "structurally designed." An Appendix Note is proposed to describe the kinds of building elements that are intended to fall into the latter category.

Referenced Standards for Materials, Components and Installation - Sentences 5.1.4.2.(3), 5.2.1.2.(1)

It is proposed to reference CSA S478, "Guideline on Durability in Buildings," in Article 5.1.4.2. to provide guidance on current good practice to minimize the probability of premature failure. Agreement by the Standing Committee on Environmental Separation (SCES) that the standard should be referenced was a factor in the inclusion of this reference in the 1997 British Columbia Building Code.

The SCES also proposes to provide guidance on good practice with regard to acceptable indoor conditions [Sentence 5.2.1.2.(1)] by adding a reference to Part 6 which in turn references handbooks and standards of the American Society of Heating and Refrigeration Engineers, such as ASHRAE 55, "Thermal Environmental Conditions for Human Occupancy," on thermal comfort.

Eliminating Lengthy Lists of Referenced Standards - Article 5.1.4.3.

The provisions that reference material, component and installation standards do not identify all the possible materials or components that may be used to serve particular functions in environmental separators or assemblies exposed to the exterior. The inclusion of all possible standards within these provisions would be cumbersome and many standards would be repeated in other Sections.

It is proposed to add a general provision [Article 5.1.4.3.] that would reference Table 2.7.3.2., Documents Referenced in the National Building Code of Canada, rather than repeatedly listing applicable standards on a provision by provision basis. This new provision would also reference specific standards that are not captured in Table 2.7.3.2. as a result of references by other parts of the Code. Consequently, it is proposed to delete the current lists of standards in Sections 5.3. to 5.6., and 5.8. and to combine the corresponding Appendix Notes and reference them from the new Article. This approach reverts in large part to that used prior to the NBC 1995.

Exceptions to Basic Requirements - Appendix Notes A-5.8.2.1., A-5.5.1.1.

Questions have been raised as to when the exceptions apply to the basic requirements regarding heat, air and moisture transfer. It is proposed to add Appendix Notes or to expand existing ones to provide information regarding air leakage, vapour diffusion, precipitation ingress and ingress of moisture from the ground.

"Minimize" - Appendix Notes A-5.4.1.1., A-5.5.1.1., A-5.6.1.1.

Because Part 5 is generally written in performance terms, many provisions require that some action be taken to "minimize" the occurrence of particular phenomena. An explanation of the term, however, is only provided in the context of heat transfer and condensation. It is proposed to add Appendix Notes to explain the term as it appears in other contexts.

Performance Requirement for Control of Air Leakage and Vapour Diffusion - Articles 5.4.1.1. and 5.5.1.1.

The current requirements for controlling air leakage and vapour diffusion begin with the specification of acceptable solutions, i.e. the installation of an air barrier system and a vapour barrier. Changes to Articles 5.4.1.1. and 5.5.1.1. are proposed to present the basic requirements in more performance-based terms and to recognize the role of venting to achieve the intents of the requirements. These changes were instigated, in part, by a proposed change to Sentence 6.2.2.7.(1) which references Part 5 for requirements related to the venting of attics and roof spaces.

Heat Transfer and Ice Damming - Sentences 5.3.1.1.(1), 5.3.1.2.(1)

Proposed changes to the heat transfer control requirements acknowledge that providing means to dissipate heat can be as important as providing means to control heat transfer in some instances (e.g., in reducing the likelihood of ice damming). It is proposed to add an Appendix Note to provide additional information and to cross-reference the new provisions from Section 5.6., Precipitation.

Sound Transmission - Sentence 3.3.4.6.(2), Section 5.9.

In keeping with the general approach to organize requirements in the Code according to design and construction disciplines, it is proposed to transfer the sound transmission requirements from Part 3 to Part 5 [Section 5.9.]. This recognizes that those involved in the design of environmental separators, rather than fire safety specialists, are concerned with constructions to control sound transmission.

Recommended Maximum Air Barrier System Leakage Rates - Sentence 5.4.1.2.(1), Appendix Note A-5.4.1.2.(1)

Part 5 does not specify limits on air barrier system leakage rates; Appendix A does provide recommended levels but does not explain clearly what these limits relate to and thus incorrect assumptions are often made. The proposed change to the Appendix Note states explicitly that the specified leakage limits are intended to apply only to the opaque portions of the building envelope.

Related Proposed Changes to Other Parts of the Code

Part 1 - Article 1.1.3.2.

It is proposed to add definitions to Article 1.1.3.2. for the terms "assembly," "component" and "material," which are used frequently throughout Part 5, and Appendix Notes to provide additional information.

Part 2 - Subsection 2.3.5.

The SCES is proposing to add Subsection 2.3.5. which would require that information be provided on the design of environmental separators and elements exposed to the exterior, as do the subsections on fire and structural safety, as well as HVAC design.

Part 3 - Article 3.3.4.6.

As noted above, the existing sound transmission requirements are proposed to be transferred from Article 3.3.4.6. to Section 5.9.

Special Change

The Canadian Commission on Building and Fire Codes has authorized the issuing of two special code changes without submitting them for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Application - Sentences 5.1.1.1.(1), 5.1.2.1.(1)

These special changes, which were approved by the Commission in 2001, expand the application of Part 5 to elements exposed to the exterior, whether or not they are environmental separators. The existing provisions were restructured to clearly identify the new scope and application of Part 5. These special changes are included in the public consultation.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NBC, stakeholders are strongly encouraged to review and comment on the entire package of changes.

During this code cycle, the Standing Committee on Building and Plumbing Services concentrated on updating the National Plumbing Code and so the revisions to the HVAC requirements of the NBC are few. Some of the important changes are as follows:

Required Ventilation - Sentences 6.2.2.1.(1) and (2)

The current wording is all encompassing and does not leave room for discretion in terms of the types of spaces that can do without ventilation. This causes conflict with ANSI/ASHRAE 62, "Ventilation for Acceptable Indoor Air Quality," which exempts closets and rooms that are not continuously occupied from the requirement to be ventilated. This change removes the conflict.

Natural Ventilation - Sentences 6.2.2.2.(1) and (2)

The current requirement does not permit acceptance of an alternative to mechanical ventilation. This is a handicap where climatic conditions may allow the provision of ventilation by means other than mechanical. This change would permit natural ventilation where climatic conditions make it feasible, subject to the presentation of engineering data to the authority having jurisdiction.

Ventilation of Storage Garages - Sentences 6.2.2.3.(1) and (2)

These provisions have been updated to include a reference to diesel-fuel-powered vehicles and will be reviewed in the future to address other fuels, such as propane and natural gas.

Air Duct Systems - Subsections 6.2.3. and 6.2.4.

Subsections 6.2.3. and 6.2.4. have been revised and consolidated into one subsection. They had overlapping requirements and their application was not clear. The revised requirements are clear and easier to enforce.

Air Washers and Evaporative Cooling Sections or Towers - Article 6.2.3.15.

This Article was revised to add the reference to NFPA 214, "Water-Cooling Towers," and to remove the subjective reference to combustible materials. New cooling towers use combustible materials such as fibreglass and PVC, and having the old requirement was a barrier to the upgrading of cooling towers in Canada. The new materials do not corrode or rust and thus require lower maintenance.

Carbon Monoxide Alarms - Article 6.2.4.1.

Carbon monoxide infiltration in homes with attached garages has resulted in deaths, and this change is meant to address this risk. It is proposed that CO detectors be required in buildings that contain a residential occupancy and a fuel-burning appliance or a storage garage.

Although this summary identifies significant proposed changes for the next edition of the NBC, readers are strongly encouraged to review and comment on the entire package of changes.

Relocation - NFC Section 5.8.

It is proposed that provisions currently located in NBC Subsections 8.2.2., Fire Safety at Demolition Sites, and 8.2.3., Fire Safety at Construction Sites, be relocated to the National Fire Code.

The changes are proposed on the basis that the NBC is a design document that regulates a completed building. Part 8 is an anomaly in that it deals with the control of hazards during the construction or demolition processes. This aspect would be more appropriately situated in the NFC; therefore all operational fire safety requirements currently in the NBC will be relocated to the NFC and a proper cross-reference will be established.

Although this summary identifies significant proposed changes for the next edition of the NFC and the NBC, readers are strongly encouraged to review and comment on the entire package of changes.

Post-Disaster Buildings - Part 1, Part 2

It is proposed that provisions regarding post-disaster buildings no longer be in Part 9. This proposal is actually manifested in proposed changes to the definition of post-disaster buildings in Part 1 and in changes to Part 2, which covers the assignment of various types of buildings to the different parts of the Code.

Lateral Load Resistance - Subsection 9.4.1., Article 9.23.10.2.

Lateral load resistance is often overlooked in the design of Part 9 buildings because many Part 9 buildings, especially houses, have a lot of inherent lateral load resistance. However, larger houses with non-traditional configurations (e.g. open floor plan, two-storey high rooms), which are becoming more common, and other types of buildings that fall under Part 9 may not have this inherent resistance. It is proposed that Part 9 define configurations (combinations of braced walls and openings) where lateral load analysis would be required. In areas with high seismic loads-located mainly in south coastal British Columbia-or very high wind loads (e.g., Pincher Creek, Alberta; Harrington Harbour, Quebec; Cape Race, Newfoundland), lateral load analysis would be required regardless of building configuration.

Snow Loads - Sentence 9.4.2.2.(1)

Failure of roofs under snow loads is the most common structural failure in Canada-generally in larger, non-Part 9 buildings. For this reason, the Standing Committee on Structural Design is proposing that the ground snow loads in Appendix C be changed from a 1-in-30-year return period to a 1-in-50-year return period. This would result in an increase in ground snow loads, and thus roof snow loads, of about 10%. Roofs would have to be built accordingly to be able to support these new snow loads. However, failure of roofs under snow in Part 9 buildings is far less common, so it is difficult to justify a 10% increase in roof snow loads and require stronger roofs for these buildings. It is therefore proposed to continue to include the 1-in-30 ground snow loads, which would apply to Part 9 buildings, in Appendix C, and to add the 1-in-50-year loads, which would apply to non-Part 9 buildings.

Stairs, Handrails and Guards - Section 9.8.

A Task Group produced a package of proposed changes on this subject, including a number of relaxations to certain requirements (e.g., 45° winders, combined straight and curved stairs in a flight).

Structural load criteria for guards are proposed. The loads are similar to those required in Part 4 though somewhat less stringent for guards within dwelling units.

Spatial Separation - Subsection 9.10.14.

Subsection 9.10.14. on spatial separations has been repeatedly adjusted and added onto over the years so that now it is one of the most complicated portions of Part 9. Extensive reorganization and clarification (without actually changing the requirements) is proposed to make this Subsection easier to use.

Insulated Concrete Form (ICF) Walls and Reinforced Masonry Foundations - Subsections 9.15.1., 9.15.2., Articles 9.15.3.3.-9.15.3.7., 9.15.4.1., 9.15.4.4., 9.15.4.8., Subsection 9.20.17.

A package of changes is proposed that provides detailed prescriptive requirements for engineered insulated concrete form walls for small houses of simple configuration. The changes would be incorporated into the requirements regarding foundations and above-ground walls.

Similarly, a set of changes is proposed that permits masonry foundation walls to be higher for a given thickness if the masonry incorporates reinforcing [9.15.2.3.(2), 9.15.4.1.].

Support of Decks - Article 9.4.3.1., Sentence 9.12.2.2.(7), Articles 9.17.2.2., 9.23.6.2.

It is not clear how the current requirements on foundations and lateral resistance apply to constructions supporting decks. The Province of Nova Scotia asked that this issue be addressed in response to cases of inadequate design and construction, and catastrophic failures. A package of proposed changes clarifies the application of existing requirements, provides prescriptive solutions for compliance with existing performance requirements, and identifies exceptions and alternative solutions to existing requirements.

Keeping the Rain Out - Sentences 9.25.4.2.(1) and (2), Subsections 9.27.1.-9.27.3., Appendix C

A submission from staff at the Canadian Construction Materials Centre proposes additional prescriptive requirements for cladding to provide more information on how to meet the existing performance requirement. As well, the Province of Nova Scotia, at the urging of the Nova Scotia Home Builders' Association, submitted a proposal that the Code require a vented air space behind cladding. Information from British Columbia identified a number of problematic constructions that are not addressed prescriptively. Together, these developments prompted the development of an extensive set of proposed changes relating to the protection of buildings from precipitation ingress:

• A set of simple prescriptive requirements addresses junctions between walls and roofs or decks.
• Protection from precipitation would be described in terms of two planes of protection, the first being the cladding and the second being the sheathing membrane and flashing, with or without a drained and vented air space.
• All residential buildings would be required to be constructed with two planes of protection (no face-sealed cladding). In high moisture load regions, the two planes of protection would need to be separated by a capillary break. Normal vinyl or metal horizontal strip siding placed over sheathing paper would satisfy both of these requirements.
• The proposed prescriptive requirements for flashing identify additional locations where flashing is needed to divert water to the exterior and specify minimum extensions, slope and end dams. The proposal requires flashing under windows and doors where the sills are not self-flashing, i.e., they do not extend over the cladding below and do not have a drip on the underside of the sill.

To identify high moisture load regions, a new climatic indicator, the moisture index, would be added to the table of climatic data in Appendix C. This is a single number that reflects both the amount of rainfall that the location receives and the duration of drying periods. It is based on research conducted as part of IRC's Moisture in Exterior Wall Systems (MEWS) project. As one might expect, coastal areas will tend to have high moisture indices and prairie areas will tend to have low moisture indices.

Maximum Temperature of Water Supplied to Fixtures - Sentence 9.31.6.1.(2), Appendix A-9.31.6.1.(2)

It is proposed to regulate the maximum temperature of hot water supplied to every fixture in residential occupancies to 49ºC. This change is being proposed to reduce the number of burn and scald injuries. Hot tap water in the house is responsible for a high number of injuries, particularly to small children and the elderly. The temperature reduction can be achieved by various means.

Ventilation - Section 9.32.

A Task Group was formed to address the difficulties industry was having in complying with the mechanical ventilation requirements in Section 9.32. The Task Group developed, and the Standing Committee agreed with, a package of proposed changes to these prescriptive requirements. The proposed version of Section 9.32. includes the following changes:

• The outdoor air duct to a forced-air heating system would be required to have both an adjustable damper and a mechanical damper. The airflow in the duct must be measured and the damper adjusted accordingly to ensure that excessive cold air does not flow over the furnace's heat exchanger. The mechanical damper must open only when the principal ventilation fan is in operation.
• If spillage-susceptible combustion equipment is present, all exhaust devices, other than the principal ventilation fan (e.g., bathroom and kitchen exhaust fans), would be required to be linked to make-up air fans of the same capacity. If no spillage-susceptible combustion equipment is present, an exhaust-only ventilation system can be used. The dwelling must have a forced-air heating system or a similar air-circulating system linked to the principal ventilation fan to ensure that the outdoor air drawn in through the building envelope (the only source of outdoor air in such a system) is circulated evenly throughout the dwelling.
• If the mechanical ventilation system could lead to depressurization of the dwelling, and the dwelling includes an attached garage, the dwelling would be required to have carbon monoxide detectors in various locations.
• Designing the ventilation system in compliance with CAN/CSA-F326, "Residential Mechanical Ventilation Systems," continues to be an acceptable alternative.

Carbon Monoxide Detectors - Article 9.32.3.9.

In addition to the CO detector requirement mentioned above, there is an alternate, more comprehensive CO detector requirement proposed in the public consultation package. CO detectors would be required in any dwelling that has any form of combustion equipment or an attached garage, regardless of the configuration of the ventilation system. A similar change is proposed to Part 6 of the NBC and thus would apply to all residential buildings, regardless of size.

Changes Resulting from the Attribution of Objectives

The NBC's objectives were established following the public consultation of 2000-2001. A few requirements that cannot be linked to any of these declared objectives are proposed for deletion or modification.

These include:

• The requirement that a door be provided for every water closet room would be eliminated [9.6.2.1.(1)].
• The requirements for door width in dwelling units would be simplified: 810 mm in entrances and 610 mm in all other cases [Table 9.6.3.1.].
• The requirement for higher ceilings in certain rooms would be eliminated [Table 9.5.3.1.].
• The requirement that windows be provided in certain rooms in dwelling units, even if electric lighting is available, would be eliminated. However, most bedrooms would still be required to have windows for purposes of ventilation and emergency egress [Table 9.7.1.2.].
• The requirements that interior steel columns and beams be painted would be eliminated [9.17.3.3.].

Other Proposed Changes to Part 9

• The requirement that windows providing emergency egress from bedrooms be openable from the inside "without special tools or knowledge" would be clarified [9.7.1.3.].
• Section 9.13. would be reorganized to clarify the application of the requirements regarding the control of soil gas ingress, and to present the requirements for dampproofing, waterproofing and soil gas control in separate subsections.
• Loose-fill insulation would be permitted in basement walls [9.25.2.4.(4)]. A special change permitting loose-fill insulation in ceilings sloped up to 4.5 in 12 was approved by the Canadian Commission on Building and Fire Codes in 2002 and is included in the public consultation [9.25.2.4.(2)].
• A reference to Part 5 would be introduced where the prescriptive building envelope requirements do not address spaces intended to be operated at high humidity over the heating season [9.25.4.2.(2)].
• The wording of the provisions regarding soil movement would be revised to clarify that they apply to the pyritic shales found in the St. Lawrence River valley [9.12.3.3., 9.14.4.1.(1), 9.16.2.2.].

Special Changes

The Canadian Commission on Building and Fire Codes has authorized the issuing of two special code changes without submitting them for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Snow Loads - Sentence 9.4.2.1.(1)

The present simplified approach to the calculation of snow loads in Part 9 is restricted to wood-frame construction. A special change has been approved by the Canadian Commission on Building and Fire Codes which extends this simplified approach to structures made of any material and where the structure has a high degree of redundancy created by the closely spaced, repetitive members of frame construction, where the total roof area does not exceed that for Part 9 buildings (regardless of firewalls), and where there are no obstructions on the roof that would contribute to significant snow accumulation.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NBC, stakeholders are strongly encouraged to review and comment on the entire package of changes.

Part 2 -Article 2.1.3.5.

It is proposed that all system installation requirements located in NFC Sections 6.2., Portable Extinguishers, 6.5., Automatic Sprinkler Systems, and 6.8., Special Fire Suppression Systems, be relocated to Part 2, Building and Occupant Fire Safety. (Refer to the proposed changes on 2.1.3.4., 2.1.3.5., 2.1.5., 6.2., 6.5., 6.8.) The related testing, inspection and maintenance requirements will remain in Part 6.

Plenum Cables - Sentence 2.4.1.1.(5)

It is proposed to add a Sentence requiring the removal of abandoned cables from plenums. This would control the accumulation of consecutive generations of communication cables and other abandoned cables in plenums, and limit the amount of combustibles in plenums.

Part 3 - Table 3.2.7.1., Subsection 3.2.9.

It is proposed that Table 3.2.7.1., Small Quantity Exemptions for Dangerous Goods, be revised to address concerns raised by regulators regarding the storage and/or display of dangerous goods. More specifically, these changes incorporate segregation and quantity limitations for newly introduced Packing Group I and II oxidizers, single trip propane cylinders, and flammable and combustible liquids displayed in large mercantile occupancies (i.e., "Big Box Stores").

It is proposed that Subsection 3.2.9., Indoor Storage of Ammonium Nitrate, be completely revised. Collaboration between major stakeholders and certain provinces has resulted in changes that more closely reflect current industry practices and related NFPA Standards.

Part 4 - Section 4.12.

It is proposed that Subsections 4.3.15., 4.3.16. and 4.4.6., which deal with leakage detection of storage tanks and piping systems for flammable and combustible liquids, be replaced.

To this end, a new Section 4.12. has been developed through input from industry and regulators. It reflects current technologies and practices. The proposed changes establish new minimum required levels of system leakage testing at the commissioning stage, as well as minimum levels of continuous in-service monitoring.

Part 5 - Sections 5.4., 5.5., Subsection 5.6.1.

It is proposed that NFC requirements that have become obsolete be replaced with established and recognized standards.

• The design, operation and maintenance requirements in Section 5.4., Spray Coating Operations, would be replaced with a reference to NFPA 33, "Spray Application Using Flammable or Combustible Materials."
• The requirements in Section 5.5., Dipping and Coating Processes, would be replaced with a reference to NFPA 34, "Dipping and Coating Processes Using Flammable or Combustible Liquids."
• The requirements in Subsection 5.6.1., Industrial Ovens, would be replaced with a reference to NFPA 86, "Ovens and Furnaces."

Part 6 - Section 6.4.

It is proposed that Sections 6.4., Standpipe and Hose Systems, 6.5., Automatic Sprinkler Systems and 6.6., Water Supply Systems for Fire Protection, be replaced with a reference to NFPA 25, "Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems."

The NFPA 25 standard addresses testing and maintenance requirements that are currently not addressed in the NFC, specifically for standpipe systems and water supplies used for fire protection.

Special Change

The Canadian Commission on Building and Fire Codes has authorized the issuing of one special code change without submitting it for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Inspection, Testing and Maintenance of Standpipe and Hose Systems - Sentence 6.4.1.1.(1)

Changes to NFPA installation standards have resulted in inspection, testing and maintenance procedures being relocated to NFPA 25. These procedures are not currently reflected in the NFC and authorities have consequently been unable to ensure adequate testing and inspection of standpipe and hose systems as there are no relevant requirements in the NFC. This special change remedies the situation.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NFC, stakeholders are strongly encouraged to review and comment on the entire package of changes.

Harmonization of Venting Requirements in the NPC

There are three versions of venting requirements currently in use across Canada: the NPC version, the Ontario version and the British Columbia version. These different venting system approaches have common elements but they use different definitions and nomenclature. In essence, all approaches result in plumbing systems that work, but trades people working across Canada have to follow the specific approaches for each jurisdiction so as not to run into disapproval from regulators. Thus harmonizing these requirements will make the transition to a single national code much easier and make life a lot simpler for the trades.

Harmonization of CSA B64.10, "Standard for Backflow Prevention Devices," and the NPC - Subsection 6.2.

The NPC and standard CSA B64.10, "Backflow Prevention Devices - Selection, Installation, Maintenance, and Field Testing," contain conflicting and overlapping requirements. This problem gives rise to concerns about the application of, and the priority given to, each document in the field. Substantial changes to the backflow requirements in NPC Subsection 6.2. are proposed based on a Task Group's recommendations. In addition, it is proposed to expand Article 6.2.4., which deals with backflow from fire protection systems, to include new requirements and definitions dealing with different classes of fire protection systems.

Revised Definitions - Article 1.3.2.

Due to the harmonization of the NPC and CSA B64.10 venting requirements, it is proposed to introduce a number of new defined terms in the NPC.

Macerating Toilets - Sentence 2.2.2.(8)

Macerating toilets have been available for some time and it is proposed to add them to the NPC. They would have to conform to CSA standard B45.9, "Macerating Systems and Related Components," and would be a viable alternative in situations where it is difficult or impossible to connect to a drainage system. For example, they are practical in cases where a toilet is required to be installed but where a drainage system is not easily accessible, such as in a basement. In macerating toilet systems, the discharge can be pumped to a drainage line by means of a small bore pipe. The intent is to provide a solution for difficult installations: these systems are not to be considered an alternative to regular water closets. Their use is to be restricted to situations where connection to a gravity drainage system is not available.

Maximum Temperature of Water Supplied to Fixtures - Sentence 2.10.7.(1), Appendix A-2.10.7.(1)

It is proposed to regulate the maximum temperature of hot water supplied to every fixture in residential occupancies to 49ºC. This change is being proposed to reduce the number of burn and scald injuries. Hot tap water in the house is responsible for a high number of injuries, particularly to small children and the elderly. The temperature reduction can be achieved by various means.

Water Hammer Arresters - Sentence 2.10.15.(1)

It is proposed that field-fabricated devices consisting of capped vertical pipe stubs that act as water hammer arresters no longer be acceptable. Experience has indicated that these devices cease to function after some time; they tend to fill up with water. The use of pre-manufactured water hammer arresters would reduce the likelihood of failure or rupture of water distribution systems.

Air Admittance Valves - Article 2.10.16.

It is proposed to recognize air admittance valves for limited applications, such as island sink venting and in renovations. Since these valves allow the entry of air into the drainage system, they eliminate the need to connect to a venting system. Thus, they are ideal for renovations where a plumbing fixture may be installed far away from a venting system.

Drains in Elevator Pits - Sentence 4.3.5.(1)

Drains in elevator pits are currently not addressed in the NPC. The addition of this provision would remove that shortcoming and ensure that appropriate sumps are provided and that backflow prevention precautions are taken where these drains are added.

Dishwasher Connections - Sentence 4.5.1.(6)

This proposed change deals with connections for dishwashing machines equipped with a drainage pump. If this connection is not done properly, trap seals can be depleted.

Cleanouts in Health Care Facilities - Sentence 4.7.4.(5)

In health care facilities, fixtures that come into contact with human body fluids and blood pose a risk to maintenance workers dealing with the rodding and cleaning of plugged drain lines. It is proposed to locate the cleanout above the flood rim level of the fixture being served which would prevent the surcharge from splashing workers.

Shut-off Valves for All Fixtures in Houses - Article 6.1.3.

This proposed change clarifies the wording of the current NPC requirement and makes the installation of shut-off valves on all fixtures mandatory. This would entail an additional cost in the short run but would provide ease of maintenance and reduce the number of complaints.

Island Sink Venting - Appendix A-4.8.2.(2)

It is proposed to add examples of how to vent island sinks in the Appendix. These types of installations have never been addressed in the NPC. This provision would make it easier for an enforcing authority to accept island sinks and ensure compliance.

There are numerous proposed changes that contain editorial revisions to NPC requirements to make them easier to understand and enforce. As well, some requirements have been updated to remove references to outdated products, such as aluminum DWV pipes and polybutylene pipes.

Special Change

The Canadian Commission on Building and Fire Codes has authorized the issuing of one special code change without submitting it for public review until now. The Commission issues special code changes in advance of public review when, in its opinion, a situation exists that is potentially dangerous or that restricts the appropriate use of materials, appliances, systems, equipment, methods of design, construction procedures, industrial processes, methods of operation or storage facilities. These changes are identified by a statement in the "Rationale" section of the Proposed Change Forms.

Special Change: Temperature and Pressure Relief for Hot Water Tanks - Sentence 6.1.7.(2)

It was proposed to add this provision mandating the installation of temperature- and pressure-relief valves on all water heaters which would eliminate certain potential safety hazards, such as the discharge of steam or water, and the risk of explosion.

Although this summary endeavours to identify the more significant proposed changes considered for the next edition of the NPC, stakeholders are strongly encouraged to review and comment on the entire package of changes.