I have just put a new lining in my loft access and cut a hatch from 18mm ply to fit the gap almost exactly. I chose 18mm ply as it doesn't flex as much as 12mm and it should offer better insulation than the hardboard that was there before! I want the hatch to swing down as I have a fitted ladder. The ladder came with one of the special retaining latches that releases if you push upwards gently. I am a bit stuck for hinges though. The hatch sits inside the lining so I don't think a normal hinge will work. I think that if I tried this it would not swing clear enough and I obviously cannot screw into the side of the hatch as it is ply. Would something like an inset hinge here work? Obviously these are for cabinets, but viewed from below this is pretty much what the lining and hatch would look like. https://www.rockler.com/articles/display_article.cfm?storyid=27&cookietest=1 Or an 18mm cranked hinge, but I cannot seem to find these anywhere. I can draw a diagram of what I mean if this is not clear, but some advice on what hinges (and where to get them) would be great.