The Lake Governor
Yeah i know, OCD mode kicked in and i could not stop...my screw fetish knows no boundaries!!!
So you reckon D&D takes about 10mm. I have already placed all the boxes on and ran cables through 20mm PVC conduit. So i actually need to leave a gap about 20mm+ deep if I D&D as it is.
If the dots are "bigger" (stick out more) would that give me enough contact knowing i can only press them down to about 20mm of the solid wall? Difficult to answer i know without actually seeing it but, i will not have time to correct the knockout boxes depth before my handy helper comes in.
Alternative is, i delay everything and install some battens maybe 47mm*20mm or thereabouts (in stock) nail them to the wall and screw the boards onto that. However, the battens would possibly have areas where they are discontinued due to the hor/vert PVC conduit.
Anyway thanks for the advice and i will make sure to put twice as many screws, if that is what i go for!
Have a nice day.
Do not leave a 20mm gap behind the board when doing D&D. We had a job where the builder asked us to do just this so I contacted BG. They said there was a very, very strong chance that the adhesion would fail at that thickness. In an ideal world even a 25mm box should be let in the wall a little.