How do I make assumptions in FirstRate5 about window awnings?

  • Awnings,
  • FirstRate5
  • All States
Last Updated: February 20, 2020


I’m curious to know a bit more about the assumptions made in the thermal software package, FirstRate5 about window awnings.  Obviously, there are many different awnings on the market. Could you advise what the packages assume (in terms of projection, vertical offset, shading %, etc)?

The reason I ask is that I’m modelling a dwelling and we want to see what type of awning would best shade for the morning sun (which makes a room quite hot).


My understanding is that awnings in FirstRate5 are generic retractable type on offset brackets or similar, that have heavy shade/blockout fabric. If nominated it is assumed that they are operated as for internal blinds to assist thermal performance at appropriate times. They are fully retractable when passive gain is beneficial and extend down vertically to shade glass from low angle solar exposure.

Accordingly, not all varieties of awnings will be modelled with exact precision but we know that vertical shading on east and west windows in summer that ensures the sun does not hit the glass is highly recommended. Sun hitting those windows in cooler months is beneficial.

Any horizontal shade device can be dealt with as an eave over windows that can have seasonal shading percentage defined.