If I have a 2-d architecture drawing (e.g. a plan/ a section etc.) and I want to extrude it to make it a volume (e.g. a wall), is there any difference if I make it using the ExtrudeSRF command (switching on the solid option) or the ExtrudeCRV command (Using in addition the Cap command to make it closed volume)? I’m not sure which way is better? and rather one way makes the model less heavier?
If you do not have surfaces, you cannot use ExtrudeSrf.
In theory at least, a “solid” made from a planar curve with ExtrudeCrv>Solid should be identical to a solid made by first using PlanarSrf on the curve and then ExtrudeSrf on the surface.
The above is assuming you have UseExtrusions turned off. Otherwise, the result of an extrusion from a planar curve will be an extrusion object, whereas the extrusion from the surface will be a polysurface.
In practice, there shouldn’t be a real noticeable difference, so you shouldn’t need to worry about which Extrude to use. The quality of the curve/surface from which you extrude is more important.