I seem to recall at some point that a glass floor was not a candidate for mob spawning (which would be nice given that one cannot place torches on glass). However, I can't seem to confirm that information at the moment... is ittrue? (i.e. if I have a glass roof, and a glass loft, do I need to worry about somehow keeping it lit)?
Mobs don't spawn on glass, ice and half steps, so your loft should be safe as per the minecraft wiki. Spiders can climb glass walls, so you may want to add a small overhang or a row of ladders if there's an entrance.
No mobs except for spiders (it seems like as of 1.5.1) can spawn on glass. Spiders require a 3x3 area to spawn in. If you place halfslabs so that you have 2x2 cubes of non-opaque blocks and halfslabs around them, they will not spawn. But if you place glass on the same y axis and 2x2 cubes of non-opaque in them, for some reason, they spawn. Don't believe me? Try it. I did it 5 minutes ago.
protected by Studoku 14 hours ago
Thank you for your interest in this question.
Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.
Would you like to answer one of these unanswered questions instead?