Floors

A floor is defined as part of the building envelope. It could either separate conditioned spaces from unconditioned spaces (such as the ground or outdoor air), or separate two conditioned spaces.

There are three main types of floor systems to consider. First, the bottom floor – this one sits directly on the ground. Then there's the internal floor, which is the subfloor found within the building itself. And finally, the external floor – typically exposed and often cantilevering out from a level above the ground.

For each of these, the floor can be optimised based on its total R value, solar absorbance, and the type of exposure it has, whether it's external, adiabatic, or in contact with the ground. You can also adjust properties like thickness, density and heat capacity. These advanced options can be found by toggling the 'hide advanced' or 'show advanced' setting.

Specify A Floor

Floor specifications are typically set in the Envelope side panel. But for those looking for more control at the Zone level, where a floor varies construction method or exposure, you can determine zone-specific floors.

As Default - Selecting a floor system as a design enables quick specification of a floor system by adopting the default wall specification for the project.

From Template - Selecting a floor system from a template enables quick access to supplier specifications.

From Design - Selecting a floor system from a design enables quick access to a floor system you have created and saved in your Project. Once selected, all associated floors must be updated within the design, saved, and then reselected.

As Concept - Selecting a floor system as a concept enables quick specification of a floor system from baseline (low performance), moderate (typical performance) or enhanced (high performance). Once selected, all associated floors can be updated.

Add a zone-specific floor by selecting a zone and navigating to the 'Zone Floor' button. Left-click 'Select Bottom Floor', and you will be presented with various options to nominate the floor performance. These included 'From Template, 'From Design', As Concept' and 'As Default'.

Specification 39 - Sub-floor Calculator

The Sub-floor Calculator is designed to expedite the calculation of the floor R-value. It considers parameters such as the perimeter, slab area, and wall thickness. This is particularly useful in the context of a slab-on-ground structure with direct contact with the soil.

In accordance with NCC 2022, the calculator's computations are based on Specification 39, relating to sub-floor and soil thermal performance. In the H1-AS1 guidelines, the calculations refer to F.1.2 Performance tables designed for determining slab-on-ground floor R-values.

Calculate an NCC 2022 sub-floor R-value by selecting the 'Specification 39 - Sub-floor Calculator'. Adjust the 'perimeter', 'slab area', and 'wall thickness', as required. Once the Floor R-value is generated, make a note of it and then copy the determined value to a Concept Design. Then click 'Done'.

H1/AS1 - Slab Calculator

The Sub-floor Calculator is designed to expedite the calculation of the floor R-value. It considers parameters such as the perimeter, slab area, and wall thickness. This is particularly useful in the context of a slab-on-ground structure with direct contact with the soil.

In the H1-AS1 guidelines, the calculations refer to F.1.2 Performance tables designed for determining slab-on-ground floor R-values.

Calculate an H1-AS1 sub-floor R-value by selecting the 'Section F.1.2 - Slab Calculator'. Adjust the 'Floor Type', 'Floor Insulation Type', 'External Wall Type', 'Perimeter', 'Slab Area', and 'Wall Thickness', as required. Once the Floor R-value is generated, make a note of it and then copy the determined value to a Concept Design. Then click 'Done'.

H1/AS1 & J1V3 - Heated Floors

A heated floor can be accounted for locally or for the entire model. Once selected, the H1 or J1V3 requirements are adjusted in the reference models.

Add a Heated Floor by selecting the floor to be determined as a Heated Floor or by navigating to 'Floors' under 'Envelope'. Next, under 'Bottom Floor', select the 'Add Heated Floor ' icon 'and hit 'Save'.

Add Air Floor

An Air Floor is a feature that enables air exchange (0.35 ACH) between two zones to be accounted for within a model. This could be an opening on a floor between two zones. Air Floors can only be applied between Zones with the same conditioning profile. For example, they can be used between two conditioned Zones but not between a conditioned and unconditioned zone.

Add an Air Floor by selecting the floor to be determined as an Air Floor and then selecting the 'Using Envelope Settings' in the left panel. Next, select 'Select Internal Floor' and then 'Air Boundary'. Thereafter, select the 'Air Boundary ACH' of the internal floor and hit 'Save'.

Exposure setting

An exposure setting refers to characterising a building's external surfaces in terms of their orientation and exposure to different weather conditions, such as sun, wind, and precipitation. The exposure settings help define how the building surfaces interact with the surrounding environment, influencing energy transfer, thermal comfort, and overall building performance and can be set for external walls, roofs and floors.

External - describes floors exposed to the external environment (e.g., wind). This is nominated by default.

Adiabatic - describe surfaces next to zones with the same thermal conditions (thus, no heat transfer).

Ground Contact - describes a slab with direct contact with ground temperatures. Ground temperatures are set under Settings.

Set the exposure setting of your Wall, Roof or Floor in the Envelope area or locally at the Aspect level. First select the Aspect you would like to update and then select 'Concept' from the options. Next, choose an option for the Concept Fabric and hit 'Select'. Open the dropdown menu to select the appropriate 'Exposure' setting and hit 'Save'.