Back box chase too deep

[Chris85]

Hi guys,

Background is that I'm trying to prep my house as much as possible before I get a proper elecrucian in to do any main electrics work, to try keeping costs down.

As part of the work I've chased out the walls for electric back boxes but I've chased a bit too deep in places so it's hard to get the back boxes flush and level. I've read about using shims etc. My worry about shims is that if the backbox needs changed in future for any reason itd be a pain to re-set so I'd like to try getting the finish as best as possible.

I was thinking about rigging up some sort of tool that would essentially be a longer piece of wood (higher/longer than the chase) to give level against the wall, with a smaller (correct depth) piece of wood or metal attached which I could then use as a guage/level. I'd then fill the chase a bit with mortor, and use this tool to smooth it to the correct depth for a backbox.

Does this seem like a sensible aproach? Or are there reasons you'd avoid this?

The other option is to use shims and try filling in behind the backbox to take the shape/depth of it but i find it hard getting the mortor behind the fitted box.

Any advice would be great.

Thanks 

Chris

 

[Chris85]

Hi guys,

Background is that I'm trying to prep my house as much as possible before I get a proper elecrucian in to do any main electrics work, to try keeping costs down.

As part of the work I've chased out the walls for electric back boxes but I've chased a bit too deep in places so it's hard to get the back boxes flush and level. I've read about using shims etc. My worry about shims is that if the backbox needs changed in future for any reason itd be a pain to re-set so I'd like to try getting the finish as best as possible.

I was thinking about rigging up some sort of tool that would essentially be a longer piece of wood (higher/longer than the chase) to give level against the wall, with a smaller (correct depth) piece of wood or metal attached which I could then use as a guage/level. I'd then fill the chase a bit with mortor, and use this tool to smooth it to the correct depth for a backbox.

Does this seem like a sensible aproach? Or are there reasons you'd avoid this?

The other option is to use shims and try filling in behind the backbox to take the shape/depth of it but i find it hard getting the mortor behind the fitted box.

Any advice would be great.

Thanks 

Chris

 

[Ardet R]

Put mortar or plaster into the back box hole and use an old back box pushed and wiggled into place to get a reasonable surface, then remove the back box and touch up any big gaps. If you are feeling posh you could put a plastic bag pulled tight over the back box to stop the mortar squeezing into the back box.

 

[Chris85]

Put mortar or plaster into the back box hole and use an old back box pushed and wiggled into place to get a reasonable surface, then remove the back box and touch up any big gaps. If you are feeling posh you could put a plastic bag pulled tight over the back box to stop the mortar squeezing into the back box.

Thanks, that would be so much more simple than my aproach

 

[Sharpend]

Probably better using either browning or bonding as it will stick better or a bit of plasterboard adhesive. 

 

[Chris85]

Probably better using either browning or bonding as it will stick better or a bit of plasterboard adhesive. 

Thanks. 

I've heard mention of pva being used, I assume I'm supposed to 'paint' some pva glue onto the bare brick surface before using bonding etc? And (just to make sure I'm doing it right) I assume its to be allowed to dry first? 

Thanks 

Chris

 

[OnOff]

How over deep are we talking? 

If just a bit then vac out the hole and use the cheapest something out of a gun like No Nails. Drill your fixing holes, put in your Rawlplugs in, good squirt of whatever and screw the thing in level. Let set  (if time's not an issue) then screw tight and clean up. If deeper then mortar you can even get a mortar gun. Fill in round the edges with filler.

If you've really overdone it you can get extenders, generally used if the walls have been overboarded:

https://www.ukelectricalsupplies.com/search.htm?search=Norslo+Extension

DON'T use cardboard - here's one I found:



Putting sockets in some hollow pocket breeze and I ended up putting some curly wurlys on FIRST then pushing into mortar:



You'll get a feel for what's right. Post a pic up and people will advise is best.

 

[Sidney]

Depending on the depth Gripfill would work. Fit rawl pug in wall as usual, squidge in some Gripfill to the required depth, insert backbox and screw. Wait until cured.

 

[Blue Duck]

Deeper boxes? 

Thread extenders?

https://www.tlc-direct.co.uk/Products/MK3710.html

Or go with some bonding as it's easy to make a good surface.

 

[Chris85]

(removed, seemed to publish twice!)

 

[Chris85]

It's about 10mm in one corner and 1mm in another the other 2 are somewhere between that.

I think I'll try the mortor and giggle the box a bit to set the depth aproach and see how that goes.

There are 3 (double) sockets in a row so I think that might give the quickest overall.

Many thanks guys for the suggestions, they are all very helpful and give me a few things to try.

Cheers,

Chris

 

[Chris85]

Deeper boxes? 

Thread extenders?

https://www.tlc-direct.co.uk/Products/MK3710.html

Or go with some bonding as it's easy to make a good surface.

I had already went up to a deeper box and then dad took over and got carried away, so don't want to go any deeper if I could avoid it, thanks tho

 

[OnOff]

Don't forget if fitting flat plate accessories then 25mm boxes might not be deep enough and 35mm better!

 

[kerching]

Fit as deep a box as you can

drywall adhesive is good for setting boxes in IF you can stand the smell!....makes me Gyp

blether out hole

dry fit box

drill holes

fit rawl plugs

refit box with a couple of 3" screws JUST into,the rawlplug 

gob a load of plaster/drywall/bonding whatever behind box

wiggle box into,position and square up

let gobbo set

remove big screws ( these have kept box aligned with rawlplugs whilst shoving box back)

screw gox back withnwhatevervscrew is suitable

repeat

 

[Murdoch]

Longer screws?

Or deeper back boxes?

and what the hell are you using to cut out the walls with? a sledge hammer?

 

[Andy™]

plaster with a bit cement (makes it go off quicker) in it. fill hole, push box into place. push wall plugs into plaster for use later if necessary

 

[OnOff]

Thanks. 

I've heard mention of pva being used, I assume I'm supposed to 'paint' some pva glue onto the bare brick surface before using bonding etc? And (just to make sure I'm doing it right) I assume its to be allowed to dry first? 

Thanks 

Chris

Mix the pva 5:1 with water and soak the knockout in the wall with a paintbrush. Make up your mortar mix with same stuff. Sh!t to a blanket.

Handy for cleaning up lettuced like this:



The white stuff was weird like a plaster / rubber cross!

 

[Evans Electric]

Just a couple of things you need to  keep in mind   Chris. 

The KO boxes don't need to be dead flush with the wall finish ,  they can be deeper.

The cable holes should have a rubber gromitt fitted . 

If  a 25mm  box is too deep , fit a 35mm ..if its a ridiculous depth use a 40mm .  

As said above , if you're planning to use flat plate  accessories you'll need  at least 35mm boxes.