Create HB Room from HB Surfaces Error faces do not form a closed volume

Hello all,

I am trying to build a building surface by surface. Using points as reference to create these surfaces. Somehow I get the below error:
1. Input _faces do not form a closed volume.
Room volume must be closed to access most honeybee features.
Preview the output Room to see the holes in your model.

But when I use the same points and instead of surfaces I create volumes and use the Create HB Room from Geometry, I don’t get any error message.

The final model is exactly the same. But the Surface by Surface component gives back an error, even though I know my model is a close volume.

Any solutions?
Surface by Surface (29.2 KB)


Hi @Barbarur,

For generating rooms by faces you will need to organise all faces which enclose the room into one list. So the input for creating 4 rooms should be a tree containing 4 lists. Otherwise honeybee does not understand which faces belong to one room.

Another issue regarding your model is that rooms with a hole in it are not accepted by energyplus. You should split the room into multiple rooms.

1 Like

Understood. Thank you @Erikbeeren

Hi all,

I have a comparable issue, see the image. Should I divide this kind of geometry into two objects?

So I found the solution.
The problem:
The exterior walls and the extruded walls (from the HB Add Subface) where both added to the _faces of the HB Room. This created an error because of the double walls.

Only use the hb_obj of the HB Add subface in the HB Room component. :see_no_evil: , it automatically uses windows + doors + walls, so do not add the walls double in the _faces.HB Room component.