J1V3

Most aspects of a J1V3 reference building are automated, wherever possible, to enable a consistent modelling approach. In some cases, where the building code is unclear, the reference building can be interpreted in multiple ways.

To respond to the varying interpretations of the building code, a reference building defaults to typical industry practice but can be updated, but can be updated to allow modellers to gain greater control of the assumptions behind the reference building.

Fabric Method

Fabric Method allows you to nominate whether to use single-aspect values (Method 1) or multiple-aspect backstop values (Method 2) for the reference building.

Combined Window Fraction

Combined Window Fraction allows you to nominate the window fraction for the reference building. When active, the window fraction is calculated once for the whole building. When inactive, the window fraction is calculated per building class.

Exclude Skylights

Exclude Skylights allows you to nominate the skylight strategy for the reference building. When active, skylights are removed from the Reference model. When inactive, skylights are present in the reference model.

Control Thermostat

Control Thermostat allows you to nominate the thermostat strategy for the reference building. When active, reference building Zones use either a thermostat of 21 - 24 CDB (when a 'Conditioned Space'), or 18 - 25 CDB (when a 'Transitory Space'). This setting can be controlled for each Space.

Wall R-values

Wall R-values allow you to nominate the wall R-value strategy for the reference building. When active, it uses the backstop Wall R-values exclusively. When inactive, it uses proposed Wall R-values if greater than the backstop.

Roof Solar Absorptance

Roof Solar Absorptance allows you to nominate the roof solar absorptance strategy for the reference building. When active, it uses the backstop Roof Solar Absorptance exclusively. When inactive, it uses proposed Roof Solar Absorptances if less than the backstop.

Automatic Max. Illumination Power Density

Automatic Max. Illumination Power Density allows you to nominate the maximum Illumination power density for the reference building. It determines the Zones' maximum illumination power density from Table J6.2a when active according to your Building Class and Zone Purpose. When inactive, it matches your Proposed Zone densities.

Fix Skylight Area to 5% Per Zone

Fix Skylight Area to 5% Per Zone allows you to nominate the skylight area strategy for the reference building. It determines the Zones' maximum illumination power density from Table J6.2a when active according to your Building Class and Zone Purpose. When inactive, it matches your Proposed Zone densities.

Exclude Internal Walls from Solar Admittance

Exclude Internal Walls from Solar Admittance allows you to nominate the Internal wall solar admittance strategy for the reference building. When active, it excludes internal thermal envelope walls from the solar admittance calculations.

Simulate Shading Multipliers

Shading Multipliers compares each window as completely unshaded, to windows affected by attached shading, building self-shading, and surrounding structures. Each window is assigned a unique shading coefficient, replacing the coefficient selected from the reference building shading tables. The advantage of this approach is that the actual benefit of shading devices is calculated as opposed to assumptions from within the building code.

Nominating shading multipliers can significantly increase the simulation time for energy and daylight modelling.