Start › Forums › BIM HVACTool Tutorials › Do you always need to mesh gratings? This topic has 0 replies, 1 voice, and was last updated 10 months ago by thomas.tian. Do you always need to mesh gratings? thomas.tianKeymaster August 8, 2021 at 7:43 am Often the gratings opening are very small. So in the BIM HVACTool there are two ways: You don’t think about it and mesh the geometry: Or you can use a porosity box in the BIM HVACTool: The box should enclose the geometry. The grating is then hidden during meshing in SnappyHexMesh. Like Viewing 1 post (of 1 total) You must be logged in to reply to this topic.