In my kitchen the walls are of painted plywood screwed to 2"x3"
verticals. I find that the electrical sockets have metal back boxes
of the type normally used in plastered walls. They are firmly screwed
in place to the plywood along their front edges.

Is this dangerous or merely unconventional? In particular, are the
plastic dry-lining back boxes you get these days designed to contain a
fire originating at the socket?

thanks for any suggestions,

Robert

On Jan 21, 10:11 am, RobertL wrote:
In my kitchen the walls are of painted plywood screwed to 2"x3"
verticals. I find that the electrical sockets have metal back boxes
of the type normally used in plastered walls. They are firmly screwed
in place to the plywood along their front edges.

Is this dangerous or merely unconventional? In particular, are the
plastic dry-lining back boxes you get these days designed to contain a
fire originating at the socket?

thanks for any suggestions,

Robert

I don't think it is dangerous, or particularly unusual. All the
sockets in our house were installed like that (metal boxes screwed to
battens behind the plasterboard).

I doubt a plastic dry-lining box would offer as much fire protection
as a metal box anyway? Apart from anything else they have great big
knockout holes on the sites where the clamping mechanism is.

Steve

On Mon, 21 Jan 2008 02:11:09 -0800 (PST) someone who may be RobertL
wrote this:-

In my kitchen the walls are of painted plywood screwed to 2"x3"
verticals. I find that the electrical sockets have metal back boxes
of the type normally used in plastered walls. They are firmly screwed
in place to the plywood along their front edges.

How precisely are the screws arranged? Are they between the box and
the plywood, thus simply jamming the box in place?

The normal way of securing metal boxes in this sort of wall is to
put a bit of wood between the uprights and screw the back of the box
to this. The bit of wood is generally inserted before the wall is
put up, otherwise it is difficult to fit in place.

Is this dangerous or merely unconventional?

It is more inconvenient than dangerous. If the screws are as I
surmised then the screws will no doubt eventually work lose and the
socket will fall out. This is slightly dangerous, but rather more
inconvenient.

In particular, are the
plastic dry-lining back boxes you get these days designed to contain a
fire originating at the socket?

All boxes are designed to contain fires. That is one of their
functions. If it is a new installation I would have the boxes
replaced by whoever put it in, if it is an old installation I would
replace them myself. In both cases I would have hollow wall boxes
put in.


--
David Hansen, Edinburgh
I will *always* explain revoked encryption keys, unless RIP prevents me
http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

In article
,
RobertL wrote:
In my kitchen the walls are of painted plywood screwed to 2"x3"
verticals. I find that the electrical sockets have metal back boxes
of the type normally used in plastered walls.

They're used in skirting boards etc too. They are the normal type of
backing box used for flush mounting - anything else is a 'special'.

They are firmly screwed
in place to the plywood along their front edges.

Is this dangerous or merely unconventional?

I'm not quite sure what you had expected to see.

In particular, are the plastic dry-lining back boxes you get these days
designed to contain a fire originating at the socket?

Yes- but they are specifically for plasterboard. Although no real reason
you can't use them elsewhere - apart from the fact they're ugly.

I'd be more concerned about the plywood walls in a kitchen presenting a
fire hazard. Have you taken advice about this?

--
*Some people are alive only because it's illegal to kill them *

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
David Hansen wrote:
The normal way of securing metal boxes in this sort of wall is to
put a bit of wood between the uprights and screw the back of the box
to this. The bit of wood is generally inserted before the wall is
put up, otherwise it is difficult to fit in place.

I dislike dry lining boxes in that you see the lip which spoils the look
of an expensive socket. So always use metal ones in plasterboard. I simply
fix batons (longer than the sides) either side of the opening behind the
plasterboard using brass screws and make good the heads. Some extra holes
may be needed in the box sides towards the front to get the best place for
the fixing screws to the batons. You could do the same to plywood, but
glue and clamp the batons till the glue sets since you may not want screw
heads showing or whatever.

I realise this is far too long winded for a pro in a rush, but eminently
suitable for a good DIY job or indeed anyone where appearance matters and
it's impossible to insert a noggin.

--
*Happiness is seeing your mother-in-law on a milk carton

Dave Plowman London SW
To e-mail, change noise into sound.

On Jan 21, 10:54*am, "Dave Plowman (News)"
wrote:
In article
,
* *RobertL wrote:

In my kitchen the walls are of painted plywood screwed to *2"x3"
verticals. * I find that the electrical sockets have metal back boxes
of the type normally used in plastered walls.

They're used in skirting boards etc too. They are the normal type of
backing box used for flush mounting *- anything else is a 'special'. *

*They are firmly screwed
in place to the plywood along their front edges.
Is this dangerous or merely unconventional? *

I'm not quite sure what you had expected to see.

In particular, are the plastic dry-lining back boxes you get these days
designed to contain a fire originating at the socket?

Yes- but they are specifically for plasterboard. Although no real reason
you can't use them elsewhere - apart from the fact they're ugly.

I'd be more concerned about the plywood walls in a kitchen presenting a
fire hazard. Have you taken advice about this?

That's an intersting thought. The whole kitchen internal wall is
wood: plywood inside and mahogony tongue and groove outside. Hous
ewas built in the 1960s.

Thank you all for your replies about the boxes. FYI the plywood is
quite thick (12mm i think) and the boxes are held in place by screws
edgeways (and slightly inwards) into the plywood. They seem very
firm.

R

Dave Plowman (News) wrote:
In article ,
David Hansen wrote:
The normal way of securing metal boxes in this sort of wall is to
put a bit of wood between the uprights and screw the back of the box
to this. The bit of wood is generally inserted before the wall is
put up, otherwise it is difficult to fit in place.

I dislike dry lining boxes in that you see the lip which spoils the look
of an expensive socket.

Not on mine..

In article 9b7c5ed8-047e-4e38-b223-f76800bd1b81
@c4g2000hsg.googlegroups.com, says...
I don't think it is dangerous, or particularly unusual. All the
sockets in our house were installed like that (metal boxes screwed to
battens behind the plasterboard).

Same here. I suspect newer build may have plastic boxes, but this is
1970 and everything except those I've got at are metal.

--
Skipweasel.
Never knowingly understood.

In article , says...
I dislike dry lining boxes in that you see the lip which spoils the look
of an expensive socket.

Not on mine..


Nor here, but that may be because we don't use expensive sockets.

--
Skipweasel.
Never knowingly understood.

In article ,
The Natural Philosopher wrote:
Dave Plowman (News) wrote:
In article ,
David Hansen wrote:
The normal way of securing metal boxes in this sort of wall is to
put a bit of wood between the uprights and screw the back of the box
to this. The bit of wood is generally inserted before the wall is
put up, otherwise it is difficult to fit in place.

I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.

--
*If at first you do succeed, try not to look too astonished.

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:


I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:


I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

Don't have any dry lining boxes for that reason. But unless you either fit
them before skimming or rebate them into the existing skim they are going
to show their presence with any standard socket.

But I'm allowed my foibles. ;-)

--
*Eagles may soar, but weasels don't get sucked into jet engines *

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:


I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

Don't have any dry lining boxes for that reason. But unless you either fit
them before skimming or rebate them into the existing skim they are going
to show their presence with any standard socket.

But I'm allowed my foibles. ;-)

--
*Eagles may soar, but weasels don't get sucked into jet engines *

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:


I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

Don't have any dry lining boxes for that reason. But unless you either fit
them before skimming or rebate them into the existing skim they are going
to show their presence with any standard socket.

But I'm allowed my foibles. ;-)


Of course you're allowed your foibles.

And it's true that old-fashioned flange boxes most certainly did show.

But I've installed considerable numbers of dry lining boxes of various
makes under sockets of various makes and switches of various makes and
they don't show in any of the instances in which I've installed them.

It would hardly be the end of the world if they did show, but the fact
of the matter is that they don't -- with any of the combinations of
manufacturers of sockets/switches/boxes that I've used.

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:


I dislike dry lining boxes in that you see the lip which spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

Don't have any dry lining boxes for that reason. But unless you either
fit them before skimming or rebate them into the existing skim they
are going to show their presence with any standard socket.

But I'm allowed my foibles. ;-)


Of course you're allowed your foibles.

And it's true that old-fashioned flange boxes most certainly did show.

But I've installed considerable numbers of dry lining boxes of various
makes under sockets of various makes and switches of various makes and
they don't show in any of the instances in which I've installed them.

So the flange now fits inside the fitting? Don't see how that's possible
with some fittings. The type that have basically a flat thin metal
faceplate, for example.

It would hardly be the end of the world if they did show, but the fact
of the matter is that they don't -- with any of the combinations of
manufacturers of sockets/switches/boxes that I've used.

Of course it's not the end of the world. I simply don't like these sort of
compromises in my house. What others are happy to put up with is their
business.

--
*If at first you do succeed, try not to look too astonished.

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" wrote in message
...
In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these words:

In article ,
Appin wrote:
The message
from "Dave Plowman (News)" contains these
words:


I dislike dry lining boxes in that you see the lip which
spoils the
look of an expensive socket.

Not on mine..

You've plastered over the lip? Sounds a bit fiddly to me.


No, you don't plaster over the edge of them.

You can't see them with any of the sockets I've used -- and I've just
gone to check. Not a trace. You must have bizarre sockets if a
standard dry lining box is visible.

Don't have any dry lining boxes for that reason. But unless you either
fit them before skimming or rebate them into the existing skim they
are going to show their presence with any standard socket.

But I'm allowed my foibles. ;-)


Of course you're allowed your foibles.

And it's true that old-fashioned flange boxes most certainly did show.

But I've installed considerable numbers of dry lining boxes of various
makes under sockets of various makes and switches of various makes and
they don't show in any of the instances in which I've installed them.

So the flange now fits inside the fitting? Don't see how that's possible
with some fittings. The type that have basically a flat thin metal
faceplate, for example.

The flange does not fit inside the fitting. It has to be below plaster level
or it shows. They are particularly visible with the flatplate switches and
sockets as you pointed out.

There are no dry liners in my house apart from the ones used for my mains
powered smoke alarms. The smokes look better without a horrible patress and
totally cover the liners.

Adam

In article ,
ARWadworth wrote:
But I've installed considerable numbers of dry lining boxes of
various makes under sockets of various makes and switches of various
makes and they don't show in any of the instances in which I've
installed them.

So the flange now fits inside the fitting? Don't see how that's
possible with some fittings. The type that have basically a flat thin
metal faceplate, for example.

The flange does not fit inside the fitting. It has to be below plaster
level or it shows.

That's what I thought. And although it might be simple to plaster up to it
in a new build I'm not so sure it would be easy to rebate it in and make
good on an existing plasterboard wall when adding a socket, etc.

They are particularly visible with the flatplate
switches and sockets as you pointed out.

Yes - and of course likely a different colour.

There are no dry liners in my house apart from the ones used for my
mains powered smoke alarms. The smokes look better without a horrible
patress and totally cover the liners.

I have used then when adding to a decorated room. But replaced them with
steel at re-decorating time.

--
*Laugh alone and the world thinks you're an idiot.

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:


But I've installed considerable numbers of dry lining boxes of various
makes under sockets of various makes and switches of various makes and
they don't show in any of the instances in which I've installed them.

So the flange now fits inside the fitting? Don't see how that's possible
with some fittings. The type that have basically a flat thin metal
faceplate, for example.

It would hardly be the end of the world if they did show, but the fact
of the matter is that they don't -- with any of the combinations of
manufacturers of sockets/switches/boxes that I've used.

Of course it's not the end of the world. I simply don't like these sort of
compromises in my house. What others are happy to put up with is their
business.

I'm blowed if I know what strange fittings or boxes some people use.
I've checked another three sockets I fitted a few months ago in my
aunt's house. No trace of the box visible. Also checked unfitted
sockets and switches against unfitted boxes. The fittings all
overlapped the flange of the box. And that's simply taking random boxes
and fittings.

I'm not trying to sell the idea of using dry lining boxes. However they
have a lot to be said for them and I simply haven't come across the
problem that you describe, I'm not saying it doesn't occur with ANY
combination of accessory and dry partition box, but it hasn't occurred
with any of the many combinations that I've used. In every instance the
accessory has overlapped the edge of the dry partition box and the
flange has accordingly been concealed by the accessory.

Appin wrote:

I'm blowed if I know what strange fittings or boxes some people use.
I've checked another three sockets I fitted a few months ago in my
aunt's house. No trace of the box visible. Also checked unfitted
sockets and switches against unfitted boxes. The fittings all
overlapped the flange of the box. And that's simply taking random boxes
and fittings.

I'm not trying to sell the idea of using dry lining boxes. However they
have a lot to be said for them and I simply haven't come across the
problem that you describe, I'm not saying it doesn't occur with ANY
combination of accessory and dry partition box, but it hasn't occurred
with any of the many combinations that I've used. In every instance the
accessory has overlapped the edge of the dry partition box and the
flange has accordingly been concealed by the accessory.

With metal flate plate accessories, they very obviously space the
fitting off the wall, and from the side, the edge of the cheap plastic
flange is visible which rather takes the edge off the flush effect that
has been paid for in spades. I.e. they look **** with nice fancy
fittings - probably irrelevant with (even nice) plastic fittings where
it is all much of a muchness in a white plastic way.

In article ,
Bolted wrote:
With metal flate plate accessories, they very obviously space the
fitting off the wall, and from the side, the edge of the cheap plastic
flange is visible which rather takes the edge off the flush effect that
has been paid for in spades.

Yup. Dunno about 'spades' - they tend to be about twice the price of a
quality plastic fitting. And worth every penny for some applications.

I.e. they look **** with nice fancy
fittings - probably irrelevant with (even nice) plastic fittings where
it is all much of a muchness in a white plastic way.

I've just looked at a new el cheapo plastic socket I have lying around and
it has ribs running from each corner so I don't see how the dry line box
rim can fit inside it.

--
*If you must choose between two evils, pick the one you've never tried before

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:

In article ,
Bolted wrote:
With metal flate plate accessories, they very obviously space the
fitting off the wall, and from the side, the edge of the cheap plastic
flange is visible which rather takes the edge off the flush effect that
has been paid for in spades.

Yup. Dunno about 'spades' - they tend to be about twice the price of a
quality plastic fitting. And worth every penny for some applications.

I.e. they look **** with nice fancy
fittings - probably irrelevant with (even nice) plastic fittings where
it is all much of a muchness in a white plastic way.

I've just looked at a new el cheapo plastic socket I have lying around and
it has ribs running from each corner so I don't see how the dry line box
rim can fit inside it.

Perhaps there's a bit of generalisation going on here.

Are ALL plastic accessories exactly the same dimensions?

Are the dimensions of all metal accessories identical to each other and
to those of plastic accessories?

Are the flanges of all dry-partition boxes identical in dimensions and
in relation to the accessory-fixing M3.5 machine screws?

Is there a rebade on the back of all accessories sufficient to allow the
accessory to fit OVER the flange and lie flat against the wall surface?


Clearly many accessories do fit over the flange. Others may not.

In article ,
Appin wrote:
I've just looked at a new el cheapo plastic socket I have lying around
and it has ribs running from each corner so I don't see how the dry
line box rim can fit inside it.

Perhaps there's a bit of generalisation going on here.

Are ALL plastic accessories exactly the same dimensions?

No. And things like the corner radius or profile varies between makes.
Which is very obvious when fitting to a dry lined box

Are the dimensions of all metal accessories identical to each other and
to those of plastic accessories?

Not all but some are.

Are the flanges of all dry-partition boxes identical in dimensions and
in relation to the accessory-fixing M3.5 machine screws?

Dunno.

Is there a rebade on the back of all accessories sufficient to allow the
accessory to fit OVER the flange and lie flat against the wall surface?


Clearly many accessories do fit over the flange. Others may not.

The snag is that although individual makers may list dry lining boxes
specifically for their accessories, most suppliers will only stock the one
make even although they stock a big range of accessory makes. Same as with
metal boxes. But any make of flush metal box is usually suitable for any
wiring accessory - with the exception of some grid type components, etc.

--
*Did you ever notice when you blow in a dog's face he gets mad at you? *

Dave Plowman London SW
To e-mail, change noise into sound.

The message
from "Dave Plowman (News)" contains these words:


The snag is that although individual makers may list dry lining boxes
specifically for their accessories, most suppliers will only stock the one
make even although they stock a big range of accessory makes. Same as with
metal boxes. But any make of flush metal box is usually suitable for any
wiring accessory - with the exception of some grid type components, etc.

I agree completely.

My very simple point was -- and is -- that there are many situations in
which dry lining boxes make a very neat and secure job and remain
invisible.

Appin wrote:
The message
from "Dave Plowman (News)" contains these words:


The snag is that although individual makers may list dry lining boxes
specifically for their accessories, most suppliers will only stock the one
make even although they stock a big range of accessory makes. Same as with
metal boxes. But any make of flush metal box is usually suitable for any
wiring accessory - with the exception of some grid type components, etc.

I agree completely.

My very simple point was -- and is -- that there are many situations in
which dry lining boxes make a very neat and secure job and remain
invisible.

I have used them (almost) everywhere. None are visible. You need to take
care to get them square, as there is very little margin for error when
fitting faceplates, but every faceplate I have used (some brass, some
chrome, some white plastic) has covered them completely.

In article ,
Appin wrote:
The snag is that although individual makers may list dry lining boxes
specifically for their accessories, most suppliers will only stock the
one make even although they stock a big range of accessory makes. Same
as with metal boxes. But any make of flush metal box is usually
suitable for any wiring accessory - with the exception of some grid
type components, etc.

I agree completely.

My very simple point was -- and is -- that there are many situations in
^^^^
which dry lining boxes make a very neat and secure job and remain
invisible.

If you change that to 'some' I'd just about agree. A first, I know. ;-)

--
*Cover me. I'm changing lanes.

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
The Natural Philosopher wrote:
My very simple point was -- and is -- that there are many situations in
which dry lining boxes make a very neat and secure job and remain
invisible.

I have used them (almost) everywhere. None are visible. You need to take
care to get them square, as there is very little margin for error when
fitting faceplates, but every faceplate I have used (some brass, some
chrome, some white plastic) has covered them completely.

I take it they were installed before the wall was skimmed?

--
*Why are a wise man and a wise guy opposites?

Dave Plowman London SW
To e-mail, change noise into sound.

On 22 Jan, 23:00, "Dave Plowman (News)" wrote:
the edge of the cheap plastic

Dunno about 'spades' - they tend to be about twice the price of a
quality plastic fitting. And worth every penny for some applications.

I use the cheapish "pearl nickel" TLC ones mostly, unless that doesn't
cover what I need, like grid switches, when the GET Ultimate ones
(which the TLC ones appear to be a rip off) are a good match (but
twice the price).

At TLC prices, it is more like 3x. I think they are worth the extra
too and use them whereever visible, but it adds up to enough money
that I don't want lousy white plastic flanges spacing them off the
wall and taking away from the effect.

probably irrelevant with (even nice) plastic fittings where
it is all much of a muchness in a white plastic way.

I've just looked at a new el cheapo plastic socket I have lying around and
it has ribs running from each corner so I don't see how the dry line box
rim can fit inside it.

What I meant was it probably blends together more looking from the
sides as they are both white plastic. Also as the sockets are proud
of the wall anyway, the spacing off the wall isn't going to be so
noticeable as with flush flat plates.

Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
My very simple point was -- and is -- that there are many situations in
which dry lining boxes make a very neat and secure job and remain
invisible.

I have used them (almost) everywhere. None are visible. You need to take
care to get them square, as there is very little margin for error when
fitting faceplates, but every faceplate I have used (some brass, some
chrome, some white plastic) has covered them completely.

I take it they were installed before the wall was skimmed?

No.
After. Some after painting too.

In article ,
The Natural Philosopher wrote:
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
My very simple point was -- and is -- that there are many situations
in which dry lining boxes make a very neat and secure job and remain
invisible.

I have used them (almost) everywhere. None are visible. You need to
take care to get them square, as there is very little margin for
error when fitting faceplates, but every faceplate I have used (some
brass, some chrome, some white plastic) has covered them completely.

I take it they were installed before the wall was skimmed?

No. After. Some after painting too.

Then please give the make of the boxes and sockets.

--
*Am I ambivalent? Well, yes and no.

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
Dave Plowman (News) wrote:
In article ,
The Natural Philosopher wrote:
My very simple point was -- and is -- that there are many situations
in which dry lining boxes make a very neat and secure job and remain
invisible.
I have used them (almost) everywhere. None are visible. You need to
take care to get them square, as there is very little margin for
error when fitting faceplates, but every faceplate I have used (some
brass, some chrome, some white plastic) has covered them completely.
I take it they were installed before the wall was skimmed?

No. After. Some after painting too.

Then please give the make of the boxes and sockets.

Newlec IIRC.

Sockets? MK's on the plastic mainly..some crabtrees.

The metals were 'heritage' range but not sure whose.