SESG Seminar Presentation

Impact of Building Regulations 2010 on Users of Dynamic Simulation

Dr Ya RoderickIES Ltd

© Integrated Environmental Solutions Ltd.

• Key changes in 2010 Section 6 in terms of DSM compliance simulation

• Key changes in 2010 Part L2A in terms of DSM compliance simulation

• Case study

• Design advices & recommendations

• New features of compliance simulation in IES VE

Overview


Section 6.1: Achieving the BER

•The 2010 Section 6 is intended to achieve a 30% reduction in carbon dioxide emissions compared to the 2007 standards.

•Target Emission Rate (TER) calculation -For heated and naturally ventilated buildings use

-For heated and mechanically ventilated buildings use

Section 6 Key Changes

TER = Cnotional x (1-0.15) x (1-0.10) TER = Cnotional x (1-0.15) x (1-0.15) x (1-0.26)

2007 Section 6 2010 Section 6

Improvement on 2002 standards made by 2007 guidance

10% building integrated LZCT benchmark

Improvement on 2002 standards made by 2007 guidance

Building integrated low carbon equipment benchmark

2010 improvement factor needed to deliver a 30% improvement on previous standards

TER = Cnotional x (1-0.20) x (1-0.10) TER = Cnotional x (1-0.20) x (1-0.15) x (1-0.26)


Section 6.2: Limits on construction U-values

•Limiting area-weighted average U-values for Actual Building are lower than the 2007 Regulations.


Type of element

2007 Section6 2010 Section 6

(a) Area weighted average U-value for all elements of the sane type (W/m2K)

(b) Individual element U-value (W/m2K)

(a) Area weighted average U-value for all elements of the sane type (W/m2K)

(b) Individual element U-value (W/m2K)

Wall 0.3 0.7 0.27 0.7

Floor 0.25 0.7 0.22 0.7

Roof 0.25 0.35 0.2 0.35

Window, doors, roof window and rooflight [1,2]

2.2 3.3 2.0 3.3

Notes:

1.Vehicle doors or similar large doors should have a maximum U-value of 1.5 W/m2K.2.There is no maximum U-value for display windows


Section 6.3: Limits on system efficiencies

•Minimum requirements for system efficiencies are higher than the 2007 Regulations.




Section 6.5: Limits on lighting efficacy

•Minimum requirements for lighting efficacy has been introduced. -General lighting

-Display lighting The installed lighting capacity comprises lighting fittings with lamps having an average initial efficacy of not less than 22 lamp lumens per circuit watt.At least 95%of the display lighting capacity in circuit Watts is provided by lighting fittings with an efficacy not less than 22 lamp lumens per circuit watt.

•Limiting air permeability (Section 6.2)-Notional BuildingAir permeability of the notional building must be 10 m3/m2.h at 50 Pa.

-Actual BuildingAir permeability of 10 m3/m2.h at 50 Pa is recommended value. No backstop value is set.Air-tightness test is required on or after 1 May 2011

Note:

Air permeability should not exceed 7 m3/m2.h at 50 Pa for a shell only building and testing should be carried out both at completion of the shell and again when the fit-out is completed.



NCM Activity Database


• Both building types and activity have been revised.

• Example changes of room activity: - Classroom being rebranded as 'Teaching area’;

- Cellular and open plan offices being combined as a standard office;

- Inclusion of Misc.24hr activity which cover data centers, server rooms and heavy plant spaces

- NCM room activities of ‘Domestic Bathroom’, ‘Domestic Bedroom’, ‘Domestic Circulation’, ‘Domestic Dining Room’, ‘Domestic Kitchen’, ‘Domestic Lounge’ and ‘Domestic Toilet’ are NOT used in Scotland.

2007 Building type 2010 Building type


Fuel CO2 Emission Factors

•CO2 emission factor for electricity is 22.5% higher than under 2007 regulations.

•Electrical loads increasingly dominant in the overall CO2 emissions.

•CO2 emission factor for grid displaced electricity has dropped. As the difference between grid supplied electricity is much smaller, the credit awarded to renewable technologies has reduced.

•CO2 emission factors for biogas and biomass has dropped and they are much less than natural gas. The credit awarded here has increased.


Fuel type2007 Section 6(kgCO2/ kwh)

2010 Section 6(kgCO2/ kwh)

Natural Gas 0.194 0.198

LPG 0.234 0.245

Biogas 0.025 0.018

Oil 0.265 0.297

Coal 0.291 0.35

Anthracite 0.317 0.318

Smokeless Fuel (inc. Coke) 0.392 0.344

Dual Fuel (mineral + wood) 0.187 0.206

Biomass 0.025 0.013

Grid Supplied Electricity 0.422 0.517

Grid Displaced Electricity 0.568 0.529

Waste Heat 0.018 0.058


Notional Building

•Notional building form


Building type


Windows and doors as % of the area of insulation envelope wall

Rooflights as % of area of roof

Windows and doors as % of the area of insulation envelope wall

Rooflights as % of area of roof [3]

Residential (non-domestic) 30 20 30 0

Offices, shops and building for entertainment and assembly purpose

40 20 40 0

Industrial and storage buildings

15 20 15 10


Notional Building

•Notional building form


Actual building

2007 Section 6 Notional building

2010 Section 6 Notional building


Notional Building

•Notional building constructions

-Most construction U-values stay the same as in the 2007 Section 6, except for: Display window U-value (6.0 W/m2K -> 5.7 W/m2K ) High usage entrance doors U-value (6.0 W/m2K -> 2.2 W/m2K )

-Smoke vents and other ventilation openings such as intake and discharge grilles should be disregarded and their area substituted by the relevant opaque fabric (roof or wall).

-Solar and daylight transmittances of glazing constructions are higher compared to the corresponding values in 2007 Section 6.

-Thermal capacity of construction elements are updated.



Notional Building

•Adjustments to heating and cooling loads (only applies to compliance check)- A factor of 0.9 applied to cooling load when service strategy includes mechanical cooling

- A factor of 1.2 applied to heating load when the heating fuel of the notional building is natural gas-A factor of 1.09 applied to heating load when the heating fuel of the notional building is oil

• Fuel types

Fuel type of a notional building is determined by whether ‘ Is mains gas available on site?’

- Where mains gas is available on site even if it does not supply any heating services in the actual building, mains gas must be used in the notional building to supply both space and water heating.

- Where mains gas is used for any space or water heating in the actual building, mains gas must also be used in the notional building.

- Oil must be used for space and water heating services in the notional building for cases other than the above two.



Actual Building

•Actual building lighting

- Design lighting power density needed for compliance analysis.

- New rules for display lighting Daylight contributes from display windows should be included in the daylight harvesting. An option for assigning automatic time switching control at zone level is available to display windows. Display lighting will be defined in terms of the average display lamp efficacy for each zone. It is editable in

VE.



Actual Building

•Actual building auxiliary energy calculation

- Auxiliary energy is the product of auxiliary power density and annual hours of operation of the heating system from the NCM activity database. The auxiliary power density is the sum of the pump and fan power density. Pump power density

It depends on the type of HVAC system and whether the pump has variable speed control (refer to Tables 10 and 11 in NCM Guide)

Fan power density

For a ventilation system that does not provide heating or cooling, fan power density is the product of the fresh air rate (NCM activity type) and the SFP defined by the user at the zone level

For mechanical extract, fan power density is the product of the user defined extract rate and the SPF defined by the user.



Actual Building

•Actual building auxiliary energy calculation Fan power density

For a ventilation system that provides heating and /or cooling, the fan power density is determined by one of the following equations which are associated to certain types of HVAC systems.

Overall, the equations above are determined by peak fresh

air supply rate (NCM activity type), space conditioning

supply rate (a function of peak space heating/cooling load),

central specific fan power and terminal specific fan power.

The auxiliary energy will be affected by Demand Control Ventilation. When the Demand Control Ventilation is based on Fan Speed Control, the auxiliary energy calculation will use a modified demand control fresh air rate instead of the peak fresh air supply rate.



Actual Building

•Actual building auxiliary energy calculation

- No user input of auxiliary power density. Users are only allowed to define the HVAC system type, specific fan powers and associated controls.

- Auxiliary energy is automatically calculated based upon: The selected NCM system type via NCM wizard The SFP for the system (refer to Table 36 in Non-Domestic Building Services Compliance Guide) The pump type selected (constant speed or variable speed) Terminal units SFP Peak heating /cooling loads (performed automatically during simulation) Demand controlled ventilation (at room level) Room extract systems



Actual Building

•Demand Controlled Ventilation (DCV)- The effect of DCV is to reduce fresh air supply

rates by a fixed factor and in certain cases to reduce the auxiliary energy associated with these air supplies.

- DCV options

Demand control based on occupancy density

Demand control based on gas sensors

- Air flow regulationDamper control

Speed control

- For natural ventilated space it has an option of ‘Enhanced ventilation’.



Actual Building

•Bivalent system

- Interface to model multiple heat sources in a system;

- Various fuel types can be specified.

- Carbon and efficiency weighted SCop calculated and applied in simulation .

Note:

In section 6, the calculated carbon factor by the bivalent system is not applied to Notional Building. However, in Part L2A, it does.


• Cooling set point for mixed modeIt allows to specify a higher cooling set point for Actual Building when the ventilation strategy is mixed

mode. The default setting in Actual Building is 25 oC and it is 27 oC in Notional Building.


Criterion 1: Achieving the BER

•The 2010 Part L2A is intended to achieve an aggregate reduction of 25% in carbon dioxide emissions compared to the 2006 standards.

•Target Emission Rate (TER) calculation

Part L2A Key Changes

TER = Cnotional x (1-IF) x (1-LZC)

Notional Building represents minimum 2002 requirements.

Improvement Factor & Low Zero Carbon Factor introduce a required improvement in performance from the 2002 regulations

Notional Building is Target.

Significant changes in Notional Building make it much more stringent than under the previous regulation framework.

The new approach has the advantage of allowing the Actual and Notional Buildings to be directly compared to identify key areas where improvement is required.

Part L 2A 2006 Part L 2A 2010

TER = Cnotional


Criterion 2: Limits on Design Flexibility

•Limiting Average U-values typically the same as 2006 Regulations and there is no longer a limiting element U-value. However, designers may need to design to better standards in order to achieve compliance.

•New limiting system efficiencies and controls are documented in the ‘Non-domestic Building Services Compliance Guide’.

•Minimum requirement for lighting efficiency now falls under Criterion 2. -General lighting should achieve a minimum initial efficacy of 55 Lumen/Watt

-Display lighting should achieve a minimum initial efficacy of 22 Lumen/Watt

•Limiting air permeability-Notional buildingAir permeability of the notional building must be 5 m3/m2.h at 50 Pa.

-Actual building Measured air permeability is not worse than the limiting value of 10 m3/m2.h at 50 Pa.



Criterion 3: Limiting the Effects of Solar Gains in Summer

•Only one means to demonstrate Compliance rather than the three methods under 2006

•It must be shown that the aggregated solar gain between April and September doesn’t exceed a benchmark level.

•Benchmarks are predetermined for each location. Side-lit spaces will be based on the exposed perimeter of the zone and roof-lit activities will be determined from the floor area.

•Applicable to all regularly occupied spaces regardless of space conditioning type.

•Analysis is based on CIBSE TRY weather data meaning that results can be extracted from a Criterion 1 analysis rather than performing a separate study.



Criterion 3: Limiting the Effects of Solar Gains in Summer



Notional Building

•Notional building form-NCM Activities categories spaces as Side-lit, Roof-lit or No lit. Side-lit: offices, circulation etc.Roof-lit: warehouse space, etc.No-lit: void, plant, cinema, theatre, etc.

-Notional spaces will have either windows or rooflight but not both.

-Windows in the notional building will form a strip across the whole facade that’s either 1.5m tall or 40% of the surface area, which ever is the lesser of the two.

-The 2010 notional building has less glazing than the 2006 regulations notional building resulting in reduced fabric losses and solar gain.



Notional Building

•Notional building construction-Building U-values are lower than the 2006 Notional Building and lower than the Criterion 2 Requirements.

-The actual building will likely need to have similar properties in order to avoid higher loads than the Notional Building.


Exposed ElementPart L2A 2010

U-value (W/m2K)Part L2A 2006

U-value(W/m2K)

Roofs 0.18 0.25

Walls 0.26 0.35

Exposed Floors 0.22 0.25

Windows/Rooflights 1.8 2.2

Vehicle Access Door 1.5 1.5

Pedestrian &High Usage Door

2.2 2.2

Internal Walls 1.8 2.0

Internal Floor (view from room above)

1.25 1.0

Internal Floor (view from room below)

1.23 1.0


Notional Building

•Notional building systems-Overall system efficiencies much better than in 2006 Regulations.

-Notional Building includes 70% efficient heat recovery.

-Generally, the Notional Building will use the same heating fuel as the Actual Building.


Systems 2006 Notional 2010 National

Gas boiler –space heating (side-lit and no-lit) 73% SCop79.2% Scop (63% biofuel)

Gas boiler - DHW heating (side-lit and no-lit) 45% SCop83.6% SCop (66.5% biofuel)

Elec heat pump space heating N/A 243% SCop

Space cooling 167% SSEER360% SSEER (270% mixed mode 27.0C setpoint)

Heat recovery effectiveness 0% 70%

Mechanical Vent SFP 2 W/l/s 1.8 W/l/s


Notional Building

•Notional building lighting-Notional Buildings Power Density based on Wall to Floor area ratio and a Power Density Curve.

-The Power Density Curve of Notional Building is intended to be representative of a lighting system with an efficacy of 55 Lumens/Watt.

-Larger, open plan spaces will have much lower Lighting Power Density than previously however smaller spaces may have a less onerous target.

-Certain activities will include Photoelectric Control to minimize lighting load in the Notional Building.



Notional Building

•Notional building auxiliary energy calculation-Pump power densityHeating only: 0.3 W/m2

Air-conditioning: 0.90 W/m2

Others (DX systems): 0 W/m2

-Fan power densityFor a ventilation system that provides heating and /or cooling, the fan power density is determined by:

SFPcentral = 1.8 W/l/s and SFPterminal = 0.5 W/l/s

For a ventilation system that does not provide heating or cooling, fan power density is the product of the fresh air rate (NCM activity type) and a SFP of 0.9 W/l/s.

For mechanical extract, fan power density is the product of the user defined extract rate and a SFP of 0.4 W/l/s. If the mechanical extract is remote, and the SFP is 0.6 W/l/s.

No Demand Control Ventilation.



Baseline Model

•Location: Glasgow

•Building type: Office

•ConstructionsWalls = 0.22 W/m².K

Ground Floor = 0.22 W/m².K

Roofs = 0.2 W/m². K

External Glazing = 1.56 W/m².K

•HVAC systemFan coil system;

Fuel type: Natural gas

Heat recovery: 65%

Auxiliary energy : 7.548 W/m2

SCop=0.825 & SSEER=2.7

Case Study

• Lighting control: PIR & occupancy sensing

controls

• Air permeability : 7 m3/m2.h @ 50Pa


Compliance results

•Part L2A

•Section 6

Case Study

Part L 2006Part L 2010

11.3% PASS - 20.6% FAIL


8.9% PASS- 11.5% FAIL


Improvements_scenario1

•Air permeability: 5 m3/m2.h @ 50Pa•Heat recovery: 70%•Fuel type: biomass

Case Study

2010 Section 6 Part L 2010

2.6% PASS- 23.4% FAIL


Improvements_scenario2

•Air permeability: 5 m3/m2.h @ 50Pa •Heat recovery: 70%•Fuel type: biomass

Case Study

2010 Section 6 Part L 2010

17.8% PASS-7.4% FAIL

• CHP • Solar panels


VE Navigator – Compliance workflows

•Logical structure to complete compliance analysis

•Help at each of the analysis

•Make notes at each stage of the project

•QA tool records when an action was completed and by whom.

Software Changes


VE Navigator – Comparison

Report

•Compares key performance indicates between the Actual and Notional Building.

•Highlights areas where the Actual Design is poorer than the Notional.

•Enables weaknesses to be identified and modified at an early stage in the design.

Software Changes


VE Navigator – Design

Recommendations

•Following a simulation, the performance of the Actual and notional building is compared.

•Based on the results recommendations will be that most effectively improve the Performance of the Actual Design.

Software Changes


• For Part L2A, as the Notional Building forms the TER directly the properties for the Notional Building can inform the designers of the approximate U-values, air tightness, system efficiency etc. That should be targeted in the Actual Design.

• Any aspect where the performance of the Notional Building exceeds that of the Actual Design will need to be compensated for with improvements elsewhere or through renewable technologies.

• Building form plays an important role. Improving day lighting will help reduce lighting loads but the effect on heating and cooling loads is less clear. Understand the tradeoffs and implications design decisions will make to help optimize performance.

• Understand the key demands placed on a building and how to design to keep these to a minimum.

Design Advice


• Consideration for low energy design an compliance should be given early in the design stage while design is flexible.

• Explore the Non-Domestic Building Services Guide and the minimum standards require.

• Use the parallel workflow nature in the <VE> of design and compliance side-by side.

• Take advantage of VE-DSM links with

- Suncast for solar shading

- Radiance for daylight dimming- ApacheHVAC for detailed plant modeling

• Use of Vista results and the Navigator Reports will help identify key areas where the building performance can be most effectively enhanced.

Design Advice


Thank you …

Questions?