Stumble block and fixtures

[Thys LOW Elektries]

Good day, a lot of people build with stumble blocks or similar hollow bricks.
The wall is hollow and the side of the bricks is about 10mm thick. My question is how do I fix the wall boxes in the wall so that they stay in one place?
The second option is to use to use the pvc Crabtree boxes with wings that lock onto the dry walls
Any advice would be welcome

[Isetech]

Good day, a lot of people build with stumble blocks or similar hollow bricks.
The wall is hollow and the side of the bricks is about 10mm thick. My question is how do I fix the wall boxes in the wall so that they stay in one place?
The second option is to use to use the pvc Crabtree boxes with wings that lock onto the dry walls
Any advice would be welcome

Foam filler works best, but gets expensive.

If its a budget job, wet the brown paper (cement bag) and pack it to fill the hollow section then pack a mix of cement and bits you chase out the wall.

I have templates for the flush boxes we use, we fill the box with wet paper, screw the box to the template, which has a 10 mm offset into the wall for dimmers, smart switches, etc, then level the template to the laser line on the wall and secure the template to the wall with the hilti gas gun.

To secure all the pipes, we use a black material straps, shoot a nail into the wall to hold the one side of the strap, flap it over all the pipes and shoot another nail to hold it, then cut the excess strap.

You might say all that wastes money, time has become the most expensive part of a project, buy cheap crap products, you add hours wasted on site.

It is bad enough trying to keep staff off their phones, throw in a couple cheap rolls of cable which take forever to strip and your profit margin flies out the window faster than your debit orders at the end of the month. ( thanks goodness I dont have any of those silly things anymore)

[Thys LOW Elektries]

Thanks for the advice