I’m working on a SketchUp model and I’m using Sefaira to understand the energy consumption of the building and how to reduce it. Part of my building is underground, so I was wondering if Sefaira considers the level 0 as ground level and how can I change the shape of the ground not to have a flat surface.
Thank you very much,
Sefaira will consider the lowest surface with the floor designation as the floor that is in contact with the ground. If you want to represent a slope running alongside your building then your best bet would be to draw the slope as an additional surface just outside of your building and tagging it as Shading (so that that particular surface will block the incident solar radiation on that portion of the wall, as if it was underground). Like so:
That being said though, do keep in mind that, the outside boundary condition of the wall will be the dry bulb temperature of the air and not the ground. So the conduction gains/losses will look like as if that wall is exposed to air and not the ground. All that the Shading surface will do is block the sunlight incident on the wall, as if that portion of the wall were underground.