tas seminar/demonstration on part l 2006 of the building regulations presented by alan jones edsl...
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Tas seminar/demonstration on Part L 2006 of the Building Regulations
Presented by Alan Jones
EDSL
February 2006
www.edsl.net
Part L2A 2006 (April)What needs to be calculated, when and how?
There are two types of calculation required:
targeted CO2 emissions
avoidance of summer overheating in naturally ventilated spaces
These calculations need to be done when:
design specifications are submitted to building control
the building has been completed
How will the target CO2 emissions rate (TER) be generated?
CO2 emissions will be calculated for a notional building and systems.This notional model will reflect Part L2 2002 standards and CIBSE TM32
TER is defined by reducing the notional emission by an improvement factorand LZC benchmark.
For air conditioned or mechanically vented buildings the reduction is 28%.
For naturally vented buildings the reduction is 23.5%
Use either accredited simulation software or SBEM for this calculation
How will the avoidance of summer overheating be demonstrated?
Comfort criteria for avoidance of summer overheating are specified for various types of naturally ventilated buildings. Usually expressed as acceptable number of hours which threshold temperatures may be exceeded. Offices not to exceed 28C for more than 20 hours per year for example.
Accredited simulation software may be used for this calculation
or average heat gains should not exceed 35W/m2 over a design day.
SBEM or Admittance procedure not applicable.
What will the compliance checking software do?
This is the procedure by which the building design is checked against all the criteria for compliance. A report is generated for submission to Building Control.
The CO2 emissions must meet the TER and minimum standards for U values, air tightness, occupation schedules and system efficiencies checked.
High system efficiencies would be flagged for inspection by the BCO.
Use either accredited simulation software or SBEM for this check
Supporting documentation would be submitted on avoidance of summer overheating.
Also O&M manuals and log book etc for completed building.
The stages of model building and analysis
Create 3D geometry model and analysis zones.
Export 3D model for daylight simulation.
Add building construction details, occupation schedules, control set points and climate data to create a building model. This model is copied to create a notional equivalent.
Simulate thermal performance of building hourly over a year to generate room loads and internal temperatures and humidity.
Add plant type and controls detail with air supply specification to create a systems model. This model has a notional equivalent created to run with the notional building,
Simulate the systems performance hourly over a year to generate energy use, CO2 emissions and plant equipment sizing.
Use notional CO2 emissions to generate the target emissions for the design.
Process the results and model input data through the Part L2 compliance checking software to prepare a report for Building Control.
If there are naturally ventilated spaces generate temperature frequencies to demonstrate avoidance of summer overheating.
An example project evaluated for Part L2 complianceThis is design undertaken by Foreman Roberts Partnership.It is a new Bio-Chemistry building at the University of Oxford.
Creating the 3D geometry modelImport CAD floor plan as a template for drawing in walls etc
Creating the 3D geometry modelAs the walls are drawn they are extruded to a defined floor to floor height
Creating the 3D geometry modelWindows are created and placed into the walls or roof
Creating the 3D geometry modelThe model is divided into analysis zones
Creating the 3D geometry modelInternal and external shading is calculated
Creating the 3D geometry model3D model exported for daylight simulation
Creating the 3D geometry model3D model exported for daylight simulation
Internal lux levels in atrium
Creating the 3D geometry model3D model exported for external daylight and sunlight studies
Creating the 3D geometry model3D model exported as 3D DWG. gbXML to Autodesk Building Systems and Cymap
Creating the building modelHourly climate data is selected for the region. There are 14 UK weather sets
External Temperature (deg.C)
-10
-5
0
5
10
15
20
25
30
35
Annual hourly data
Deg
C
External Temperature (deg.C)
Creating the building modelHourly climate data is selected for the region. There are 14 UK weather sets
Global and diffuse solar radiation
0
100
200
300
400
500
600
700
800
900
1000
Annual hourly data
W/m
2 o
n t
he
ho
rizo
nta
l
Global Radiation (W/m2) Diffuse Radiation (W/m2)
Creating the building modelHourly climate data is selected for the region. There are 14 UK weather sets
24
721
201
682
162
643
1236
0
1
3
5
7
9
11
13
15
0
20
40
60
80
100
120
140
Total No. Hours
Wind Bearing (degrees)
Wind Speed (m/s)
Wind Rose MAY-SEPT
0-20 20-40 40-60 60-80 80-100 100-120 120-140
Creating the building modelThe difference between dynamic simulation and admittance
Creating the building modelThe difference between dynamic simulation and admittance
10
15
20
25
30
35
40
Monitored performance BRE office first floor south, summer 1997
Creating the building modelThe difference between dynamic simulation and admittance
10
15
20
25
30
35
40
Simulated performance BRE office first floor south, summer 1994 weather
Creating the building modelThe difference between dynamic simulation and admittance
10
15
20
25
30
35
40
Repeated hot day simulation with beam & diffuse shading (2)
Creating the building modelThe difference between dynamic simulation and admittance
10
15
20
25
30
35
40
Repeated hot day simulation with beam shading only (3)
Creating the building modelThe difference between dynamic simulation and admittance
10
15
20
25
30
35
40
Real weather simulation with beam & diffuse shading (1)
(3)
(2)
(1)
Admittance method with no diffuse shade calculation
Creating the building modelConstruction and glazing details are selected from databases
Creating the building modelConstruction and glazing details are selected from databases
Creating the building modelA calendar is used to identify days when different activities occur
Creating the building modelOccupation schedules and heat gains are specified for the different day types
Creating the building modelThermostat control settings may be specified for the different day types
Creating the building modelThe daylight simulation can be used to calculate lighting energy savings
Lighting energy use with daylight saving
0
2
4
6
8
10
12
14
16
Annual hourly data
W/m
2
Creating the building modelFor naturally ventilated spaces window or vent opening strategies may be applied
Running a simulation and viewing the resultsAny combination of spaces and performance data may be displayed
Running a simulation and viewing the resultsData may be exported into Excel for report preparation
Laboratory temperature and loads over a winter week
0
5
10
15
20
25
7 days
Tem
per
atu
re C
0
1000
2000
3000
4000
5000
6000
7000
8000
External Temperature (deg.C) 2 lab 1 Dry Bulb (deg.C) 2 lab 1 Heating Load (W) 2 lab 1 Cooling Load (W)
Post processing the resultsA number of macros are available to produce frequently required data
0.00
1000.00
2000.00
3000.00
4000.00
5000.00
6000.00
Demand (kWh)
Daily total demand for biochemistry building
Heating Cooling Internal Solar
Post processing the resultsA number of macros are available to produce frequently required data
Peak demands for biochemistry building
0.00
100.00
200.00
300.00
400.00
500.00
600.00
700.00
Heating Peaks on Day 46,Hour 7
Cooling Peaks on Day179, Hour 14
Humdify Peaks on Day45, Hour 7
Dehumidify Peaks on Day186, Hour 14
Internal Peaks on Day 1,Hour 17
Solar Peaks on Day 139,Hour 12
Lo
ad
(k
W)
Post processing the resultsA number of macros are available to produce frequently required data
Heating Cooling Humdify Dehumidify Internal Solar
0.00
200000.00
400000.00
600000.00
800000.00
1000000.00
1200000.00
1400000.00
1600000.00
1800000.00
2000000.00
Demand (kWh)
Annual total demand for biochemistry building
Post processing the resultsBasic room loads may be sized
Post processing the resultsFrequency charts of internal temperatures may be generated
Cumulative Frequency of Resultant Temperature for YearLower level of atrium in biochemistry building
1090 1085
1018
761
410
172
0 0 0 0 00
200
400
600
800
1000
1200
20 21 22 23 24 25 26 27 28 29 30
Temperature (C)
Nu
mb
er
of
Ho
urs
Calculating energy use and CO2 emissionsA copy is made of the design building model to create the notional model
The notional building model is a copy of the design model retaining the shape, zones and occupancy.
All U-values are replaced with elementally compliant values and glazing ratios changed to be elementally compliant.
This process is automated.
The notional system, that is used with the notional building, is specified in
CIBSE TM32.
It is a standard good practice fan coil system with gas boiler and air cooled chiller.
The allocation of this notional system is automated.
Plant details may be added to the building modelGeneral plant details
Plant details may be added to the building modelFresh air supply and terminal unit
Plant details may be added to the building modelBuilding zones to be supplied by a particular system type are selected
Plant details may be added to the building modelPlant room equipment specifications are added
The system is simulated using the hourly room demandsDesign energy consumption is shown against the notional standard
Annual Energy Consumption for biochemistry
0
50
100
150
200
250
300
Design Notional
Co
ns
um
pti
on
in
kW
h/m
2
Lighting
Pumps
Fans
AHU Cooling
Room Cooling
Humidification
AHU Heating
Room Heating
The system is simulated using the hourly room demandsDesign CO2 emissions is shown against the notional standard
Annual CO2 Emissions for biochemistry
0
10
20
30
40
50
60
70
80
90
Design Notional Target CO2 Emission Rate
Em
iss
isio
ns
in
kg
CO
2/m
2 TER
Lighting
Pumps
Fans
AHU Cooling
Room Cooling
Humidification
AHU Heating
Room Heating
The system is simulated using the hourly room demandsPeak demand for all systems are calculated
Peak Consumption for the biochemistry building
0
100
200
300
400
500
600
Room HeatingConsumption
Peaks on Day 349,Hour 7
AHU HeatingConsumption
Peaks on Day 45,Hour 10
HumidificationConsumption
Peaks on Day 52,Hour 16
Room CoolingConsumption
Peaks on Day 181,Hour 15
AHU CoolingConsumption
Peaks on Day 195,Hour 9
Fans ConsumptionPeaks on Day 135,
Hour 13
PumpsConsumption
Peaks on Day 186,Hour 11
LightingConsumption
Peaks on Day 1,Hour 17
Co
ns
um
pti
on
(k
W)
The system is simulated using the hourly room demandsIndividual plant components are sized
Accredited software needs to comply with relevant BS EN ISO standards
Accredited software needs to comply with relevant CIBSE TM 33 Tests