In the Sefaira web application, how is the ground floor considered for conduction gains and losses?

The web application assumes slab on grade construction with a uniform assembly U value of:

  • Metric: 0.338 W/m2·K
  • US: 0.059 Btu/ft2·°F (approximately R-17).

The ground temperature is dynamically calculated from the weather file. It is not a constant temperature, as it had been in earlier versions of Sefaira.

Users are able to download the corresponding .idf file to manually alter inputs to run through EnergyPlus. 

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    Juan Garduno

    Thank you April!

    Would you mind sharing how to download the .idf files and manually alter input?

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    Juan Garduno

    I should clarify. I'm working on a project (15,000sf) where the ground level's east, north, and west wall are under 13' of dirt (these are retaining walls). I'm not able to model this walls as regular walls, should I model them as floors instead?

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    Marco Henriquez

    @Juan: Have you ever received an answer? Because we're having a similar issue..