Hi @ikhsan.pc ,

My first instinct is related to the way your solids are connected to eachother. For example in my expert drawing below the intersection between 2 solids is a line.

However, I’ve seen cases where seemingly intersecting objects also return weird results, that is probably because of how Dynamo handles geometry under the hood. Could you share what kinds of geometry you’re trying to compare?

Here I link the column structure with the architect’s wall, that intersection

Hmm that’s weird, I would also assume that this would result in solids. Perhaps the BimorphNodes Clash detection nodes give better results. BimorphNodes v2.1 Released with Ultra-Efficient Clash Detection and Geometry Intersection Nodes

Remove any columns which always return solids, then any walls which return solids on those columns. Then post the RVT here or elsewhere for review.