1. Update of the National Energy Code for Buildings

2. Recent history of the Energy Code development in Canada
Outline
Recent history of the Energy Code development in Canada
National Energy Code for Buildings (NECB) 2011
Impetus for updating the 1997 Model National Energy Code for Buildings
Approach used in NECB and details
This presentation will focus on two main areas:
a history of the development of national energy codes for construction
Second, I’ll be talking about the National Energy Code for Buildings (NECB) 2011 which is an update of the Model National Energy Code for Buildings (MNECB) 1997
the reasons why the decision was made to update the MNECB, and a discussion on the approach and basic philosophy used in the update, its framework, and an overview of its technical aspects

3. Model National Energy Code for Buildings 1997
History
Model National Energy Code for Buildings 1997
Prescriptive approach: building envelope, HVAC, service water heating, lighting, electrical power
Engineering approach: performance  “Performance Compliance for Buildings”
reference and proposed building modeling
Model National Energy Code for Houses (MNECH) published in 1997
The Model National Energy Code for Buildings (MNECB) was published in 1997.
The basis of the document was the prescriptive provisions found in various parts of the code dealing with building envelope, HVAC, service water heating, lighting and electrical power. The building envelope part allowed for some prescriptive trade-offs between building envelope components.
Since the publication of the previous Energy Measures, modeling methodology and tools had dramatically progressed, so that the MNECB 1997 contained a Part dealing with a whole building engineering approach on how to perform the modeling. Most of the provisions and guidelines related to this were published in a separate document entitled "Performance Compliance for Buildings“, published in In this procedure, the energy use of the proposed building is determined in accordance with the modeling approach. This is then compared to the energy used by the same building but designed to the prescriptive requirements (the reference building). The energy used by the proposed building cannot exceed that used by the reference building.
The scope of the MNECB 1997 generally addressed all buildings except for Part 9 housing. A separate energy code for Part 9 housing was published at the same time, the Model National Energy Code for Houses 1997.

4. Total life-cycle costing
History (cont’d)
Total life-cycle costing
Different construction requirements for different energy sources
Regional variations in energy costs
Not widely adopted
The requirements in both energy codes were established using total life-cycle costing. This costing involved different values depending on the principle energy source. This resulted in a variation of total energy used by buildings that have different energy sources, all other design considerations being the same. Also, the costing took regional energy cost variations into account and so requirements could vary from one region to another even if the climatic considerations were identical.
Although the MNECB 1997 was not widely adopted by the provinces and territories (in fact, only one province referenced the document), a number of government, utility, and private sector programs used the MNECB as a complement to incentive programs and to establish a baseline for new energy-efficient building design.  These programs include NRCan’s Commercial Building Incentive Program (CBIP), utilities programs in BC, Manitoba, Ontario and Quebec and LEED-Canada.
Based on the lack of adoption of the MNECB by the provinces and territories, work on the energy codes was suspended until..

5. Decision to Update
June 2005 Canadian Commission on Building and Fire Codes (CCBFC) meeting
NRCan presentation and request for update
Motion
“Moved … and seconded … that CCBFC supports, as a first phase, the work on the technical basis for the development of the revisions to the MNECB as a progeny document on condition that the necessary support and funding for the project is provided from NRCan and/or others.”
At the June 2005 meeting of the CCBFC, NRCan requested that the CCBFC update the MNECB 1997 based on declining energy resources available to Canadians and the high levels of demand on energy by buildings. The CCBFC agreed to a first phase that required that provincial/territorial support from the building construction departments be demonstrated and that the project be funded by NRCan and/or others. The actual motion that was approved is shown on the slide.

6. Decision to Update February 2007 CCBFC meeting
Building Energy Codes Collaborative (BECC)
business plan
P/T support
funding from NRCan
February 2007 CCBFC meeting
“Moved by …, seconded by …, that the updating of the MNECB as a progeny document based on the BECC business plan be approved, subject to:
the process to develop the document would follow the policies and procedures of the Commission
the work would not compromise the capacity to complete the current and ongoing priorities of the coordinated codes development system”
The Building Energy Codes Collaborative (BECC) was established. BECC was a provincial-territorial-federal committee supported by the Council of Energy Ministers, the Assistant Deputy Minister Steering Committee on Energy Efficiency and NRCan with a mandate of pursuing the update of the MNECB as a stand-alone document. The BECC put together a business plan that contained letters of support for addressing energy requirements for buildings in a code from both the energy and building construction provincial/territorial ministries, as well as a commitment of funding from NRCan.
BECC presented this business plan at the February 2007 meeting of the CCBFC. The CCBFC agreed to update the MNECB 1997 on the conditions that it follow the code development process established by the CCBFC and that the work not compromise the work being undertaken on the other model code documents. The actual motion that was approved is shown on the slide.

7. First meeting in December 2007 Task groups
NECB 2011
Standing Committee on Energy Efficiency in Buildings (SC-EEB) formed in 2007
First meeting in December 2007
Task groups
Building Envelope
HVAC and Service Water Heating
Lighting and Power
Performance Compliance
Code Consolidation
The Standing Committee on Energy Efficiency in Buildings (SCEEB) was established in 2007 to complete the technical update of the document. The first meeting of the SCEEB was held in December 2007, and the work is proceeding on an accelerated basis that is scheduled to produce the National Energy Code for Buildings (NECB) in 2011.
The bulk of the work is being addressed by task groups of the SCEEB. They are the Task Groups on building envelope, HVAC and service water heating, lighting and electrical power, building energy performance compliance, and code consolidation. The task groups are responsible for specific Parts of the Code. In addition, the task group on code consolidation, which is comprised of the chairs of the other task groups and of the SCEEB, is overseeing the development of all the other task groups to ensure that there is consistency in the approach and to provide overall guidance.

8. Energy used by the building Paths of compliance
NECB 2011
Objective-based
Energy used by the building
Paths of compliance
Prescriptive path
Trade-off path (within the Part)
Performance path
Simple payback approach
The NECB 2011 will be in objective-based format as are the National Building, Plumbing and Fire Codes.
The NECB 2011 will have a pure energy objective in that it will address energy used by the building and will not codify factors and costs related to energy source and local variations. The provisions will, of course, vary depending on climate zone as determined by heating degree days.
It will have three compliance paths: a prescriptive path, a trade-off path that allows for trade-off within a part only, and a performance path.
Costs will not be codified, though cost analysis, using a simple payback approach, will be conducted to support the technical changes.

9. Task Group on Building Envelope
Maximum overall thermal transmittances (U-values) will not differ for different assembly construction
Thermal requirements categorized by climate zone, defined by heating degree days – six Canadian climate zones
Thermal requirements will be fuel source neutral
Limitation on the fenestration and door to wall ratio in the prescriptive path
Air barrier requirements are being introduced for building envelope assemblies
Now, let's get into some of the finer details of what you will see in the NECB We’ll start with the work of the Task Group on Building Envelope, whose mandate it is to update Part 3 – Building Envelope of the MNECB 1997.
- Air leakage requirements are being introduced for building envelope assemblies
- The overall thermal transmittances (U-values) will not differ for different types of assembly construction. In other words, there will be one U-value for roofs one for opaque walls, etc.
The thermal requirements will be given by climate zone for six Canadian climate zones.
(Zone 4: , Zone 5: , Zone 6: , Zone 7a: , Zone 7b: , Zone 8: 7000 and above)
The thermal requirements will be fuel source neutral

10. Task Group on Building Envelope (cont’d)
Existing Provisions
Table A (1)
Prescriptive Requirements – Above-ground Building Assemblies
Forming Part of Sentence (1)
Assembly Description
Principal Heating Source
Electricity, Other
Oil, Propane, Heat Pump
Natural Gas
Maximum Overall Thermal Transmittance (U-value), W/m2 ºC
Roofs
Type I - attic-type roofs
0.140
0.200
Type II - parallel-chord trusses and joist-type roofs
0.230
Type III - all other roofs (e.g., concrete decks with rigid insulation)
0.290
0.410
0.470
Walls
0.330
0.480
0.550
Floors
Type I
- parallel-chord trusses and joist-type floors
0.220
Type II
- all other floors (e.g., concrete slabs with rigid insulation)
Here is an example of the existing provisions in MNECB 1997 for maximum overall thermal transmittance for above-ground components. As you can see, there are three different roof types and two different floor types, each with different U-values depending on the principal heating source.
In the MNECB 1997, more insulation is required if the roof was an attic-type roof. More insulation is required for an attic in a building heated by electricity compared to one heated with natural gas.

11. Task Group on Building Envelope (cont’d)
Proposed Approach
Heating Degree-Days of Building Location(1), Celsius degree-days
Zone 4: < 3000
Zone 5: to 3999
Zone 6: to 4999
Zone 7A: to 5999
Zone 7B: to 6999
Zone 8: ≥ to 7000
Maximum Overall Thermal Transmittance (W/m2K)
In Contact With the Ground
Walls
0.568
0.379
0.284
0.210
Roofs
Floors 1
for 1.2 m
full area
Above-Ground Component
0.315
0.278
0.247
0.183
0.227
0.162
0.142
Floors
Fenestration 2
2.4
2.2
1.6
Doors 3
In the proposed approach, there is one maximum overall U-value for each assembly types (roof, wall, floor) regardless of the principal heating fuel.
Table 1. Proposed Thermal Requirements for the NECB 2011
Notes to Table 1:
1 – floors in contact with the ground with imbedded heating cables or heating or cooling pipes require full area insulation in all heating-degree day categories
2 - exception of overall thermal transmittance of 3.4 W/m2K for skylights not exceeding 2% of gross roof area
3 - exception of overall thermal transmittance of 4.4 W/m2K for doors not exceeding 2% of gross wall area

12. Task Group on Building Envelope (cont’d)
The maximum allowable total vertical fenestration and door area to gross wall area (FDWR) will vary by climate zone:
FDWR = 0.40 for HDD < FDWR ≤ (2.590 X 10-8)∙HDD2 – (3.516 X 10-4)∙HDD , for 4000 ≤ HDD ≤ FDWR = 0.20 for HDD > 7000

13. Task Group on Building Envelope (cont’d)

14. Task Group on Building Envelope (cont’d)
Building envelope trade-off compliance path
Scaled down version of the full performance path, considering only building envelope elements
Demonstration that the building envelope will not use more energy than it would if all components were to comply with the prescriptive path

15. Task Group on Lighting and Electrical Power
Lighting requirements are generally being harmonized with ASHRAE
Additional requirements for automatic control devices, including automatic daylighting controls
Lighting power allowances for building exteriors will be introduced for more exterior lighting applications
Next, looking at the work of the Task Group on Lighting and Electrical Power whose mandate is to update Part 4 (lighting) and Part 7 (electrical power) of the MNECB 1997.
To give you a sense of some of the changes coming forward for the lighting part there will be:
- a general harmonization of lighting requirements in the NECB with the proposed lighting requirements of ASHRAE 90.1 / 2010
- additional requirements for automatic control devices
- requirements for more exterior lighting applications

16. Task Group on Lighting and Electrical Power (cont’d)
Lighting (cont’d)
Lighting Power Density (LPD) tables updated
Lighting Power Densities
Using the Building Area Method
Building Area Type W/m2
Automotive facility 9.79
Convention center 11.30
Courthouse 11.51
Dining: bar lounge/leisure 10.87
Dining: cafeteria/fast food 10.01
Dining: family 10.11
The lighting power density tables will be updated.
The table shown is an excerpt from the lighting power density tables in the MNECB 1997.

17. Task Group on Lighting and Electrical Power (cont’d)
Lighting (cont’d)
LPD tables updated
Lighting Power Densities Using the Building Method
Building Type(1)
Lighting Power Density (W/m2)
Automotive facility
8.8
Convention centre
11.6
Courthouse
11.3
Dining: bar lounge/leisure
10.7
Dining: cafeteria/fast food
9.7
Dining: family
9.6
Dormitory
6.6
Exercise centre
9.5
Fire station
7.6
Gymnasium
10.8
Health-care clinic
9.4
Hospital
13.0 …
The new lighting power densities (LPDs) were determined by updating the lighting models that form the basis for the LPDs.
Based on the illumination requirements for the space type, the lighting equipment combinations are considered and the required power for each of those combinations is determined . The model conducts multiple simulations to arrive at the lighting power densities for each of the space types.

18. Task Group on Lighting and Electrical Power (cont’d)
Lighting (cont’d)
New lighting trade-off compliance path
for interior lighting only
quantify the impact of daylighting/daylight dependent and other controls
compare the overall lighting energy use of a building to a prescriptive baseline
A simple trade-off compliance path will be introduced in the lighting part of the NECB This trade-off path allows the user to quantify the impact of daylighting / daylight dependent control and other controls on the energy use, in order to compare it to the overall lighting energy use of a building defined by the prescriptive path within the NECB. This gives the lighting designer more flexibility in applying the LPDs.

19. Task Group on Lighting and Electrical Power (cont’d)
Few technical changes are proposed
New voltage drop requirements for feeder conductors and branch circuit conductors

20. Task Group on HVAC and Service Water Heating
For prescriptive path, values for efficiency ratings, insulation thicknesses, etc., are being updated
New requirements
maximum temperature set points for vestibules
more requirements for when cooling is installed
more requirements for heat recovery systems
Next we’ll look at the work of the Task Group on HVAC and Service Water Heating whose mandate is to update Part 5 (HVAC) and Part 6 (Service Water Heating) of the MNECB 1997.
To give you a sense of some of the changes coming forward for the HVAC and Service Water Heating parts:
- The efficiency ratings of HVAC and Service Water Heating equipment and the minimum pipe insulation thicknesses are being updated in the prescriptive paths.
New requirements for maximum temperature set points for vestibules;
New requirements when cooling is to be installed
More requirements for heat recovery systems, and
New requirements for solar thermal service water heating equipment, where installed.

21. Task Group on HVAC and Service Water Heating (cont’d)
New HVAC and service water heating trade-off compliance paths that consider system efficiencies as opposed to individual component efficiencies – would include losses through the ducts and pipes
The HVAC and service water heating parts are also proposing the introduction of a new “simple” trade-off path (I.e. within the Parts only) A methodology has been established to calculate the system efficiencies as opposed to individual component efficiencies. This methodology, for example, takes into account system losses through the ducts and pipes. Compliance for the overall system will be shown when the weighted sum of the individual component efficiencies is not exceeded and provided certain limitations are met. .
With respect to both the trade-off path and performance path, there will be some limitations imposed on the HVAC and service water heating equipment. For instance, regardless of the compliance path chosen, the minimum levels in National and provincial energy efficiency acts will be maintained.

22. Task Group on HVAC and Service Water Heating (cont’d)
Trade-off Path for HVAC (similar for SWH)
where
i - counter for number of components included, as per Article , for the given HVAC system
α1i - constant weighting factor to link the component efficiency variations of component i to system efficiency variations as per Article
α2i - first order weighting factor to link the component efficiency variations of component i to system efficiency variations as per Article
α3i - second order weighting factor to link the component efficiency variations of component i to system efficiency variations as per Article
ToVi - Specified value of component i for the proposed building as per Article
BaVi - Base value specified for component i the reference building as per Article
This table demonstrates what the proposed new trade-off path could look like. The overall system efficiency would be based on the component efficiencies and how each one was weighted for it’s effect on the overall efficiency. The methodology behind a trade-off tool included over 20,000 modeling computations to determine the weight factors.

23. Task Group on Building Performance Compliance
Contents of the supplement “Performance Compliance for Buildings” is being shifted to either the Code, the explanatory appendix to the Code, or a proposed users guide
Criteria/systems that are in the proposed building will be included in the reference building (e.g., cooling)
The goal is to base compliance on building energy targets – for a subsequent version of the NECB
Next we’ll look at the work of the TG on Building Energy Performance Compliance whose mandate is to update Part 8 of the MNECB 1997.
The requirements within the supplement “Performance Compliance for Buildings” will be moved to within the body of the code, into the appendix of the code or into a proposed user’s guide for the NECB, which should be available shortly after the Code is published.
The ultimate performance goal of the National Energy Code for Buildings is to establish an energy target or budget based on class of building, and could take the form of energy used per square meter of building floor area or per cubic meter of building. The modeling procedure of the performance compliance path would then produce an energy usage that could be compared against the energy target. This was not achievable for the 2011 version but will be the goal for the subsequent edition.

24. NECB 2011
Public review of the proposed changes will take place in the fall of 2010
A public review of the proposed changes to the Model National Energy Code for Buildings will take place in the fall of 2010.
Additional information on the code development process and the National Energy Code for Buildings can be found at the Canadian Codes Centre website:

25. NECB 2011
Questions?
Are there any questions?