Huge Mesh to Surface and exporting to STL

Hello!

I have made a huge mesh representing a topography. In addition I want to model the houses as simple boxes and then export the file as stl.

I have made a gh definition that builds up the houses but just on surfaces. So do you think it is worth to try to convert the mesh into surface or not? I am asking because i read that it is better to have meshes when the intention is to export to stl.

In case you think it is worth to convert the mesh, do you have any suggestion how to do it? I tried the most I found in here but the mesh is just too big.

Thank you in advance