Concealed door closers

Is this the sort with a little chain in the doorjam?

ISTR the guts of the are pushed inside the door, with a fixing also on the doorframe. They won't know or care what's the other side of the doorframe.

Thass the one.

Guess it all comes down to getting a solid fixing, then. The springs on these things are pretty strong (have to be, of course).

Used to be made/branded PERKO? If you don't have the bit of metal they come with to hold the chain extended whilst you put the screws in, then jam a small nail in the chain link instead.

hth

Bob

Indeed they do, but I see no reason why you shouldn't fit the barrel into the frame if there were a studwork void behind it. It would get you around the problem of drilling a deep 25mm hole into the door which may be as thin as 32mm.