Plasterboard depth of back boxes

[vini]

Just had a discussion with a builder where he told me that metal back boxes have to be fixed at a certain depth. The front edge of the box should be about 3mm depth from the front surface of plasterboard (12mm). I am unaware of any depth requirements regarding plasterboard and metal back boxes, height requirements yes and distance from corners etc. but it is a new one on me as to depth. He did not want fast fix boxes, in case they came out even though the wall was being tiled after the first fix.

Am I missing something or am I dealing with a smart ****?

 

[buzzlightyear]

Just had a discussion with a builder where he told me that metal back boxes have to be fixed at a certain depth. The front edge of the box should be about 3mm depth from the front surface of plasterboard (12mm). I am unaware of any depth requirements regarding plasterboard and metal back boxes, height requirements yes and distance from corners etc. but it is a new one on me as to depth. He did not want fast fix boxes, in case they came out even though the wall was being tiled after the first fix

tell the builder you have long screws!

 

[telectrix]

the front edge of the box should be just below surface, but there's no stipulated figure. i suppose his reasoning ( if a builder has any) is that the metal box would contain any arcing.

 

[Andy78]

I agree really. The metal box should be behind the front edge of the board, but not behind the rear side. I wouldn't even consider fast fix boxes on a new job.

 

[buzzlightyear]

is the builder dob and dabbing the boards in ?

 

[buzzlightyear]

The metal box should be behind the front edge of the board

it depends on the plasterer and how good he his .

 

[telectrix]

Flob-a-Dob-a-Dob.

 

[Andy78]

it depends on the plasterer and how good he his .

If slap n dabbed yes. If wooden framed then it's down to the person fixing the box.

 

[Squid]

Tell the builder you have "qualifikations" and he should do as he is told,

 

[vini]

It was the 3mm that got me. It is plaster board on a wooden frame and he was placing dwangs across the studs for me to fix my boxes onto. To me there is a good practice rule rather than a precision rule

 

[Octopus]

25mm or 35mm back boxes?

 

[buzzlightyear]

It was the 3mm that got me. It is plaster board on a wooden frame and he was placing dwangs across the studs for me to fix my boxes onto. To me there is a good practice rule rather than a precision rule

on any timber frames ,I stick my own noggins for my knock out boxes .

 

[vini]

35mm

 

[mattg4321]

If he's fixing the nogs for you then I wouldn't worry!

 

[buzzlightyear]

vini ,vinni, why are the builders trying to run shot gun over you .
tell him there is only one way to hammer a nail in!