Roofs

A Roof is a non-conditioned thermal zone or space drawn on any level of a design within the Building Assessment App.

Specify a Roof

Roofs are defined at each level but can also be controlled for the entire model using a default wall or Tags. Total R-value, solar absorptance, exposure, thickness, density and heat capacity can be set for the entire wall via defaults, supplier or generic templates from a design you have created or as a concept.

Specify a roof for the entire model or via Tags under 'Envelope'. Left-click 'Roofs', and you will be presented with the default specifications set when the model is created. Left-click 'Select Top Roof' if there are no specifications to nominate the roof performance. Options included 'From Template, 'From Design', and 'As Concept'. These are further explained below.

As Default - Selecting a roof system as a design enables quick specification of a roof system by adopting the default roof specification for the project. Only available at Aspect.

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

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

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

Draw a Roof

Navigate to 'Buildings' and select 'Levels. Then select the 'Level' you would like to add a Roof, then choose 'Add Roof' or 'Edit Roof', as applicable. Next, as shown in the example below, you can select a pre-drawn roof or use the 'Draw Roofs' tool in the drawing space ribbon to draw a zone representing your roof. Multiple roofs can be drawn on any Level. You will receive an error notification when geometric clashes or inaccuracies occur in your model.

Navigate to 'Site' and Select 'Building'. Then select the Level you would like to add a Roof, then choose Add Roof or Edit Roof, as applicable. Next, as shown in the example below, you can select a pre-drawn roof or use the Draw Roofs tool in the drawing space ribbon to draw a zone representing your roof. Multiple roofs can be drawn on any Level. You will receive an error notification when geometric clashes or inaccuracies occur in your model.

Once a Roof is drawn, navigate to the zone and select. The following options are available.

Layout

• Roof Type - Determine the type of surface generated for your Roof. Additional options are presented for each type.

• Roof Offset - Raise the Roof line higher

Pitch

• Slope Method - Determine how the pitch(es) are calculated for this Roof.

• Pitch - Nominate the degrees from true North for the slope of the roof surface. When using the Single-pitch type, the roof ascends in this direction

Cavity

• Ceiling Method - Roof cavities are created above each Zone, with two surfaces - one at the external roof line and another for the horizontal ceiling.

• Insulation Position - Nominate whether the cavity is insulated at the ceiling (cold) or insulated at the roof line (warm). This is undertaken on the Envelope Tab.

• Outdoor Air Method - Nominate the method for outdoor air introduced to the cavity.

• Air Changes / Hour - Nominate the air changes per hour introduced to the cavity.

Eaves

• Typical Projection - Default projection of eaves for this Roof. Custom eave projections can be assigned for Single and Double-pitch Roofs.

Envelope

• Insulated Surface - Roof surface assigned with insulation.

• Enclosure Surface - Roof surface used to enclose cavities, if needed. For cold Roofs with a Cavity, this is the roof shell. For warm roofs, this is the ceiling surface.

Set Zone Specific Roofs

Roof specifications are typically set in the Envelope area. But for those looking for more control at the Zone level, you can determine Zone-specific Roofs.

Add a Zone specific Roof by selecting the Zone and navigating to the 'Zone Roof' button. Next, select 'Select Top Roof', and you can either select 'As Concept', 'From Design' or 'From Template'. Select 'From Template' and a prebuilt Template from any supplier. Give your template a title and click '+ Add'.