On Monday, July 4, 2016 at 7:54:40 PM UTC+1, ss wrote:
I have a rubber wedge for holding a door open, the door has a not very
powerful door closer.
The `wedge` only has the tip that will fit under the door due to low
clearance.
The wedge slips on the floor tiles usually after a few minutes and the
door closes.
Any ideas on how I could make the rubber slightly tacky to stop it
slipping ?

Make a wooden one; works on our tiled floors with strong door closers.

Jonathan