We now return to the Building & System Data dialogue to prepare for the compliance simulations. If the ‘Set Building & System Data’ button is not visible at the bottom of the screen, move the cursor into an empty space on the model workspace graphic and click once.
Building & System Data is distributed over three tabs.
First, on the General tab, fill in the address and contact details.
Then move to the Building & System Performance tab. This contains data required by the BRUKL compliance checker that collates the simulation results and generates the compliance report.
Building air permeability at 50 Pa – BRUKL requires confirmation of this air-tightness parameter, which must have a value of 10 m3/( m2·h) or less. Note that setting this parameter must be set in addition to the infiltration rates used in simulations.
Is solar gain acceptable in occupied zones without mechanical cooling (L2A paragraphs 59 & 60)? - If the building contains any occupied spaces without mechanical cooling (air conditioning), you are required to make a statement that the solar gain in those rooms has been shown to be acceptable (Criterion 3).
Method used to show compliance with L2A paragraph 60 (supply supporting documentation) - If the previous box displays ‘Yes’, the method used to demonstrate that Criterion 3 is satisfied must be indicated here. The recommended setting for <VE> Compliance methodology is Method b (temperature simulation).
Heat source efficiency - BRUKL requires the overall system heat source efficiency as an input. You may type a value or tick the box labelled ‘Derive from Apache System?’ to get the software to calculate an area-weighted average heat source efficiency for all Apache Systems used in the building.
The remaining parameters appear in the box labelled ‘Adjustment for management features’. These settings allow credit to be taken in the BER calculation for management features applied to electrical power and lighting:
Electric power factor
Lighting systems have provision for metering?
Lighting systems metering warns of ‘out-of-range’ values?
Finally, click on the Simulations settings tab, which displays the ApacheSim simulation settings that will be used in the Compliance simulations and test runs. Note that where appropriate these are shared between the Notional and Actual building, and between compliance and summer temperature check simulations. The following are the important settings:
Results file – the name you enter here (prefixed by ‘a_’ for the actual building and ‘n_’ for the notional building) will be used to store the results of the simulations, which can be viewed in Vista.
SunCast link? – tick this box if you wish to use SunCast shading data in the simulation of the actual building.
Preconditioning period – make sure (using test runs if necessary) that this is sufficient to establish a realistic starting condition for the simulations.
Other settings which you may also need to use are:
Natural ventilation air exchange? – tick this box if you have specified any ventilation by means of natural ventilation air exchanges
Use previous results for notional building? – tick this box to save simulation time if you are repeating a compliance test with changes that do not affect the notional building, for example changes to system efficiencies.
You may also change the time step, reporting interval and output options to generate more detailed results data for Vista.
Note that the weather file is forced to the appropriate TRY dataset for compliance simulations. If this file is not present compliance simulations will not be enabled.
