# Opaque Doors An opaque door is part of the building envelope separating conditioned and unconditioned spaces. It does not allow light to penetrate but can still significantly impact heat transfer between spaces. ### Specify an Opaque Door Opaque Doors (typically hinged) can be added to any aspect to be considered in energy or daylight modelling. They are generally lightweight and have little to no thermal performance. Add Opaque Doors by selecting the aspect and then select ‘Select Opaque Door’ on the Envelope tab and either 'As Concept' or 'As Default'. Specify the Opaque Door 'Total R-value', 'Solar Absorbtance', 'Thickness', 'Density' and 'Heat Capacity', as required, and then click 'Save'.

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