Can I square off a uPVC door sill which is inside a conservatory?
Looking at the exposed end of the sill, that looks like a terrible idea.
It appears to be an extrusion with a few ribs and void spaces between ribs, not a solid block. If you cut off the edge, you'll have an unsupported &quot;flap&quot; sticking out from the next rib. That seems unlikely to wear well.