Can't install light switch to wall because nothing to secure it to

[bennie1]

Hello all,

I am attempting to install a light switch in my living room, but the horizonal wooden stirps which are behind the wall, is broken directly behind the light switch, thus I have nothing to screw the light switch into, to secure it.

Furthermore, I tried to install a light switch holder (a face place with about an 2" depth (to accommodate the wiring) and i thought this might work because it uses 4 screws to secure to the wall, instead of the 2 in the light switch, but again, the same problem: the screws have nothing to secure to.

Please see the attached photos, for a clearer picture of my problem.

Any help would be greatly appreciated,

thank you in advance

 

[JohnD]

It looks like you have an L&P wall.

How old is the house?

Is this an internal partition wall? How thick? What is on the other side?

BTW your old wiring is horrible.

 

[securespark]

It may be possible to fix a batten across the hole to secure the accessory box to.

 

[Tigercubrider]

Take a bit of timber - probably 2. - 2x1 or similar.
Drill a hole through the centre and thread a piece of string through.
Wangle it through the hole and pull the string tight to hold it so it is held against the inner of the wall.
same again
Then you could fit a screw through the wall and the backing timber (pre drill a pilot hole) on each end
Screw the pattress box to that.

You might get away with not drilling through the wall and using just the pattress box to pull the wood tight.

 

[333rocky333]

You should be fixing a box in first, its not acceptable nowadays to screw a switch on with the rear exposed to the fabric of the building.
You will need to fix battening inside to secure it.

Carefully cut the lathes to the box size and fix the batten to the left and right by screwing through the plaster and laths from the front, fix the metal box to the battens via the sides, you can fill over the screw holes to the front later.
Go for a 35mm or 50mm box, easier to work with,
Use a grommet in the hole to protect wires.

If you dont mind it surface then use the existnig wood to secure some new wood, behind them, then fit your 4 hole surface box.

See this recent post of what may be involved
https://www.diynot.com/diy/threads/screw-keeps-spinning.561104/page-5#post-4854035

 

[securespark]

If using a box deeper than 16mm, you would need to fit spacer blocks on the ends of the batten so that the batten is the required distance from the plaster surface when in place.

 

[bennie1]

It looks like you have an L&P wall.

How old is the house?

Is this an internal partition wall? How thick? What is on the other side?

BTW your old wiring is horrible.

I think its about 100 years old.

The wall material is plaster with a hollow space and small, thin wooden beams running across.

 

[JohnD]

I think it is L&P


Is this an internal partition wall? How thick? What is on the other side?

There will be vertical studs, maybe two feet apart. Poke something flexible through the hole, sideways, to see where they are. It had better be something electrically insulated.

 

[bennie1]

What's L&P?

This wall is in my living room, and behind it is a small bedroom. I'd say about a foot in depth.

 

[JohnD]

Lath and plaster.

A foot thick is incredible, there must be something inside it, like structural beams, or a stone, brick or cob wall.

When you find out what it is, you can probably fix to it. Unless cob.

 

[EFLImpudence]

Lath (your thin wooden beams) and Plaster.

 

[sparkwright]

If you are happy with a surface mounted (sticks out) box, you could get a PVC one.

These allow holes to be drilled into it wherever you like without it shattering.

You 'should' be able to get two fixings into those wooden laths.

Obviously we're not there so it's hard to say for sure.

 

[bennie1]

thanks for the responses.

If I can secure a piece of wood to these wooden laths thats the best option, I suspect.

I don't know how the laths were broken, but its made it impossible to secure anything into them.

 

[bennie1]

Can i drill into expanding foam?

Perhaps if i used expanding foam i could secure the box into place?

 

[sparkwright]

Are you trying to achieve surface mounted or flush mounted?