@tmrwr1ter2 Hi! I'm not sure if they have a room for weapons. They mostly use spears and those are mostly just lying around wherever they put them, leaning against walls in random places, but if they did have a room for weapons, I'd say they'd use the slicers' hut. That hut should be on the other side of the Glade, as far from the other huts as possible, considering what goes on in there might make the others uncomfortable. (It’s not mentioned in the movie at all, but they should have a place for the slicers). Should be at least a handful of knives in there, so it makes sense they'd have weapons there too…
I hope that helps. :)