IES <Virtual Environment> Tutorial <VE Compliance> Part L2 (Version 5.8) Introduction This tutorial will show you how to use the <VE compliance> Part L2 compliance checking tool for new buildings other than dwellings. We will use a building model previously created in the ModelIT tutorial. This Part L2 tutorial assumes prior knowledge of IES s Apache software. We recommend you complete the Apache tutorial before proceeding. For more detailed help you can use the Help menu within the specific IES application, and also you can refer to the product manuals installed with the IES software. 1
Opening a previously created <Virtual Environment> project First you must open a previously created project using the File option from the main <Virtual Environment> menu. Open the project folder and select and open the MIT file within this folder. The project will then open. 2
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Switching to the <VE> Compliance> view Click the <VE> Compliance button in the Thermal group of programs. The five stages of setting up a project for a Part L2 compliance check are: 1. Setting the compliance route 2. Setting the general building data required for compliance certification 3. Setting site location and weather data 4. Setting constructions 5. Setting templates and HVAC systems The three stages to provide evidence of compliance are: 1. (ADL2 Criterion 1) Perform a carbon emissions assessment for the Actual & Notional Building 2. (ADL2 Criterion 2) Perform a check on minimum acceptable design limits for HVAC systems and constructions 3. (ADL2 Criterion 3) Perform a solar overheating study (Non air-conditioned buildings only) This tutorial will address these three stages. 4
Choosing the regulatory framework Select Regulatory Framework and choose Part L2 (2006) England and Wales. Select the ApacheSim method. Selecting the building type Make sure all rooms are de-selected. Using the building type drop down list select the Building Type (in this case choose Office). 5
Setting building and system data Click the Set Building and System Data button to enter details required for a BRUKL certificate to be created: General building information, Building & System Performance and Simulation Settings Enter building data, building owner and certifier data: 6
Enter Building and system performance data; this data is required for the BRUKL compliance certificate Acceptability of solar gain is required for all non-cooled spaces. 7
Enter the simulation settings as below. Check the SunCast link (if available). 8
Setting the site location and simulation weather data Click the Click here to set site location option to start the APlocate utility (see the ApacheSim tutorial for details). Use the Selection Wizard in ApLocate: Select the location (for general analysis) 9
Select the Site Location. Follow the Wizard through pages 1 to 4 (this tutorial does not require data on pages 2 and 3). Note that on Page 3 of the Wizard you need to press the Acquire design weather button to proceed to Page 4. 10
On Page 4 of the Wizard, select the location for the Part L2 analysis using the select button in the UK Building Regulations Part L area. Once you have done this, save the settings in ApLocate, then exit from ApLocate. 11
Defining constructions If you haven t already created constructions using the Apache Constructions Database and applied them to the model in the Apache view, you will need to do this in the <VE Compliance> view. Click the Click here to define constructions option. The Apache Constructions Database will open. Create and edit all opaque and glazed constructions to match the requirements of the current project. See the Apache tutorial for details of how to create constructions. 12
Applying constructions to selected rooms Once you have created constructions you can apply them to selected rooms or selected surfaces/openings by using the Assign Constructions button. See the Apache tutorial for details of how to assign constructions. 13
Setting up Building Templates Click the Click here to set up Building Templates option. The Building Template Manager will start. Make sure you have selected the Thermal Conditions templates. You should see the Offices template and Server Rooms template which were created in the Apache Tutorial. If they are not there, you should create them. Room conditions and Internal Gains data are defined by the DCLG, so for Part L2 analyses you don t need to define them. They will automatically be applied to rooms in the building within <VE Compliance>. The sections you need to fill in are: Building regulations tab (Building type and activity) System tab (HVAC system definition) Air exchanges tab (Air permeability) Select the Offices template. 14
Building regulations tab Select the room type from the drop down list. (choose Heated Room). Select the NCM building type (choose Office). Select the NCM activity from the drop down list (choose NCM Office: Cellular office ). System tab Here you define the HVAC System. You first need to use the View Apache Systems button. 15
The Apache Systems window will appear where you can set HVAC system data. The creation of HVAC systems will be covered in detail later in this tutorial. To save any amended settings in the Apache Systems window, click the OK button in the Apache Systems window and the window will close. Once you have defined your HVAC system(s), you can select the required system back in the System tab. 16
Air Exchange tab We need to enter the building air permeability using the air infiltration rate specified in the Air Exchanges tab: Click the Add/Edit button. Alter the infiltration rate to match the building air permeability 0.167 ach == 10 m 3 /hr/m 2 @ 50 Pa. Check the Add to template column to add this item of infiltration into the current template and click the OK button. 17
Repeat the process for the Server Rooms template, entering the same data in the tabs except for the NCM activity in the Building Regulations tab, where you should select NCM Office: High density IT work space. The templates should be created for all room types in the real building. Save the settings in the Building Template Manager, then close the Building Template Manager. 18
Setting up Apache Systems Click the Click here to define Apache Systems option to open the Apache Systems window (note that the alternative way to open this window is to use the View Apache Systems button from the Systems tab in the Thermal Conditions templates as mentioned earlier). Click the UK NCM system data wizard button. 19
Choose the appropriate HVAC system from the drop down list. In this example we will select Constant volume system (variable fresh air rate). Select properties for the Heating system. 20
Select properties for the Cooling system. Select system adjustment properties. 21
Select control corrections. Once the HVAC system is set, click OK and choose the Yes, save and apply the NCM parameters option. This will then apply all the above information to the selected system in the Apache Systems window. 22
Note: the improvement factor used in determining the Target Emissions Rate (TER) is determined by the proportion of air conditioned, naturally ventilated or mechanical ventilated zones in the actual and notional building. The improvement factor is set via the Cooling Mechanism drop down in the Cooling System area within the Apache Systems window. (The UK NCM system data wizard will fill in this variable automatically). Also note that the outside air supply settings in the Apache Systems window are not used in the Part L2 software (HVAC air supply will automatically be applied to rooms in the building within <VE Compliance> and will be defined as Auxiliary Ventilation in the Air Exchange Tab). 23
To save the amended settings in the Apache Systems window, click the OK button in this window and the window will close. Updated system data will be applied automatically to the templates where the systems are being used. Assigning thermal templates to selected rooms Select the two upper floor rooms, then click the Assign Room Thermal Template to Selection Set button. The Assign Template window will open. From the Thermal Template drop down list, select the Offices template and then click on OK to assign the information in this template to the selected rooms. Repeat the process by applying the Server Rooms template to the three ground floor rooms. 24
Viewing or editing the room data for one selected room in the actual building You can see what data is applied to the actual and notional building and this can give an indication of how the performance of the actual building can be improved. If you wish to change the thermal information for a selected room in the actual building, you can do this by first selecting the required room. Let s select the Studio. Next, click the Query button. Note that the Query facility will only be available if one room only is selected. The Room Data window will appear showing you the thermal data for the Studio which you can see is taken from the Offices template. To change an item of data, you must first break the link to the template by unchecking the Template check box. Some data in the tabs is non editable predefined NCM (National Calculation Methodology) data, but you could make changes to lighting gains and power consumptions or to the infiltration rate. 25
Viewing room data for one selected room in the notional building Use the drop down list to access the notional building. The view then shows the notional building. Select a single room and use the Query button to view the room specific data for the notional building. 26
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Note: for the notional building none of the data items are editable this is in line with the requirements of the National Calculation Methodology. Similarly, none of the constructions are editable for the notional building. In the actual building some room data can be changed (lighting gains, infiltration rates and HVAC system information) as well as construction data. An example of this will be given later in this tutorial. Use the drop down list to access the actual building again. 28
Performing compliance checks Criteria 1 and 2 Part L2 compliance checking for carbon emissions (Criterion 1) is performed by clicking the CO 2 Emissions: Part L compliance button. This will simulate the actual and notional building and produce the Building Emission Rate, Notional building Emissions Rate and the Target Emission Rate. The simulation should take a couple of minutes for this example building. Results are shown in the results tab. In this example it is clear that the actual building does not emit less carbon dioxide than the notional building (ie the BER is greater than the TER). 29
If compliance with Criterion 2 is not achieved Note that Criterion 2 is checked at the beginning of a Carbon Emission calculation. If the building fails this check a U-value check results window will appear and the simulation will be cancelled. Note: in this example the external glazing will need to be replaced by a glazed unit with a lower u- value. To do this select the whole building and select the Assign Constructions button. As described in the Apache tutorial, change the glazing to a better glazing construction. 30
You will then be permitted to perform a Criterion 1 check. 31
Performing compliance checks Criteria 3 (summertime temperature check) Click the Summer temperature check (actual building) button. The Apache simulation setting window will appear to allow you to perform a simulation over the summer months. Check the SunCast link if it is available. Click on the Simulate button. A simulation will begin which analyses the building for summertime overheating and results will appear in a table. 32
Creation of a compliance certificate The certification required for building control submission is accessed via the View Compliance Doc button in the Results tab. This creates the compliance certificate (created by the BRE tool BRUKL): 33
Viewing results in Vista If you need to, you can view the simulation results in Vista, IES s results analysis tool. To do this, click the View summary and results in Vista button. If you see a save data prompt, click the Yes button. The <Virtual Environment> will now switch to the Vista view (see the Vista tutorial for details). If a summary of building simulation performance window appears in Vista, you can close this window. Results for the actual and notional building can be viewed in Vista. The prefixes a_ and n_ identify the.aps results files for the actual and notional building respectively and s_ identifies the results for summer time overheating. Select the results files for both notional and actual building by using your mouse button and the <Ctrl> key on your keyboard. 34
Results can be viewed for Loads, Energy and Carbon. Results can also be shown per system: 35
Click the Carbon button, then select the three variables shown below. Click the Monthly Totals button in Vista. 36
Looking at the Carbon Emissions for the actual and notional building it can be seen that the system electricity use is higher in the actual than the notional building and that the lighting electricity use is the same for both buildings. To reduce the Carbon Emissions here we should consider improving the efficiency of the cooling system (system electricity), auxiliary energy (fans, pumps and control system electricity) and reduce the lighting energy usage. To do this, return to the <VE Compliance> view by clicking the <VE Compliance> button>. Reducing lighting energy usage Select all the rooms where the lighting energy is to be reduced and click the Edit Group Attributes button. 37
The Edit Group Attributes window will appear. We will reduce the lighting energy gain (which will reduce the cooling demand) and the lighting power consumption (which will reduce the electricity usage of the lighting). The sensible gain and power consumption will be reduced from 18.75 W/m 2 to 15 W/m 2 (i.e. 500 lux at 3.75 W/m 2 per 100 lux to 3 W/m 2 per 100 lux) To do this, select the Internal Gains tab, and select the Fluorescent Lighting option. Check the upper check box and select W/m 2 as the input mode. Enter 15 for the maximum sensible gain and power consumption values. Click on the OK button to apply the changes to the selected rooms 38
Reducing the system energy usage Click the Click here to define Apache Systems option to open the Apache Systems window. Reduce the auxiliary energy usage and improve the seasonal efficiencies for both the heating and cooling system. 39
After re-running the compliance check, Criterion 1 should be met. If not, you will need to make further changes and try again. Note: system efficiencies, auxiliary energy, lighting power consumption and gains used in this example are not necessarily representative of real system performance. Please refer to the Non- Domestic Heating, Cooling and Ventilation Guide for further details. This is freely available from the DCLG www.dclg.gov.uk. Please refer to the Part L2 guidance notes on the IES website for further information: www.iesve.com You have now completed the <VE Compliance> Part L2 tutorial. 40