Question Trying to hide speaker cable behind plaster board

freeflyer

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I am trying to hide my speaker cable and planned to hide it behind the plaster board. The cable routing is shown in the diagram below. There are two external walls and one internal wall, I was planning to go up and over the door frame behind the plaster board...

CablePlan2.jpg


The house was built just over a year ago, it is brick and timber frame with Kingspan insulation...

kingspan.png


I found the stud positions (using a magnet to find the nails) and marked the spacing which is 600mm. So I drilled a hole either side of the stud...

PlasterboardHoles.jpg


I asked the developer for details of the external and internal wall construction, but they weren't very helpful. They sent me this drawing and advised that I get a professional to do the work...

WallStructure.png


The drawing shows two layers of 12.5mm plaster board and a 25mm access void, but I think this is for an internal wall. Because the holes I made in the external wall has two layers of 12.5mm plaster board but only a 9mm void...

ExtWallHoles.jpg


Unfortunately I drilled into the Kingspan insulation :( I removed the media panel (which is on the same wall and can be seen in the picture where the 4 mains sockets are) to see how the wall is constructed. The face of the plaster board to the breather membrane (behind the metal back box) is a depth of 70mm. So for some reason this is different to where I drilled the two holes either side of the stud. And more worryingly, I also found a plastic pipe (highlighted in yellow) behind the media panel metal back box...

MediaPanel.jpg


I have no idea how the external wall is constructed and as for the internal wall, I don't know if it is the same as the drawing provided by the developer.

The only other option I can think of is to remove the mdf skirting board and rebate it myself, or replace it with rebated skirting board (from skirting4u). But then there is the issue of the architrave around the door which they don't sell rebated.

So it seems either method (hiding behind plaster board or hiding behind rebated skirting board) is going to be difficult.

Can anyone provide any advice or help please ? I've used conduit that you stick onto the skirting board before, but don't like this technique (looks messy and is a nightmare to remove).

It would be nice to obtain the blue prints / architecture drawings for the house, but I don't know if this is possible. Surely these must be available for any future work carried out by external contractors, such as extensions and modifications etc ? I have asked the developer how to obtain them but not had a response.

The only other information I have is this plan (which is opposite handed), but it doesn't tell me anything...

groundfloorplan.jpg
 
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Hi freeflyer

Have you thought about using "flat" speaker cable underneath you carpet. This may be easier and cheaper than channeling walls, then having to "make good" after you have installed it?
 
Hi freeflyer

Have you thought about using "flat" speaker cable underneath you carpet. This may be easier and cheaper than channeling walls, then having to "make good" after you have installed it?

Was just about to post the same, that's all I have done in both my houses, absolute doddle.
 
Unfortunately I have already bought all the cable and tools, expecting that I would be able to hide it behind the plaster board or skirting board. I have also bought all the wall plates, so these will need to be fitted into the plaster board anyway.

I was a bit unsure about the flat speaker cable because:

1 - The carpet might not fit back properly. From experience of lifting and refitting carpet, it never goes back very well. I know the professionals use a special tool when fitting the carpet and get the impression it requires skill to do so?
2 - I wasn't sure if the cable would leave a bulge under the carpet
3 - I wasn't sure if standard speaker cable (i.e. non-flat) is a better quality. The cable I am using is 511 strands of 0.1 mm, so its resistance will be less than the flat speaker cable.
 
You should be able to hide the cable behind the skirting board ok. There is usually a gap where the wall meets the floor that's hidden by the skirting, run cables straight up/down wall then along at floor level.
 
Forgive me for thinking outside the box but what about drilling right through the wall and running the cables in trunking down the external walls for the length of the room then bring them back in at the appropriate places?
 
Running cables down the external wall is an option, but it seems like more work and not as tidy. Also I would still have the issue of running it across the internal wall (where there is a door frame).

Its frustrating, because all I need to know is how the wall is constructed. But it seems that this information is top secret and confidential for some reason ?
 
OP, the disadvantages of purchasing a modern highly insulated house. :( The architect has made no plans for you to alter the layout of your living room.

In the drawings supplied by your developer, it shows a service void of 25mm, but looks as if the has been reduced to 9mm by the installer, quite typical in the way house are constructed, unfortunately these days. I would not take to drilling holes to the outside, there are membranes that you will puncture which may cause problems with damp and reduce the efficiency of the construction.

You could remove the plasterboard covered by the skirting, install your cables there, and replace the skirting with a slightly higher profile. You would then have to negotiate a route around your door frame, which may require some 'fishing' and removal of some plasterboard, and making good.

The plastic pipe, what colour is it and diameter? If it is an electrical conduit, it looks as if its run in the safe zone for electrical wiring.
 
OP, the disadvantages of purchasing a modern highly insulated house. :( The architect has made no plans for you to alter the layout of your living room.

In the drawings supplied by your developer, it shows a service void of 25mm, but looks as if the has been reduced to 9mm by the installer, quite typical in the way house are constructed, unfortunately these days. I would not take to drilling holes to the outside, there are membranes that you will puncture which may cause problems with damp and reduce the efficiency of the construction.

You could remove the plasterboard covered by the skirting, install your cables there, and replace the skirting with a slightly higher profile. You would then have to negotiate a route around your door frame, which may require some 'fishing' and removal of some plasterboard, and making good.

The plastic pipe, what colour is it and diameter? If it is an electrical conduit, it looks as if its run in the safe zone for electrical wiring.

Thanks ufo550, I am not sure whether the drawing supplied by my developer is for an internal wall or external wall, I have a feeling its for an internal wall but I could be wrong. I was wondering how the media panel can be 70mm deep, because further along the same wall the depth is only 34mm deep (12.5 mm plaster board x 2 plus 9mm void). Would they have removed ~35mm of material from the insulation block to make it 70mm deep for the media panel ?

Like you said, the last thing I want to do is cause problems with damp and efficiency etc, especially as this could void the warranty.

From what I could see, the plastic pipe was white and the diameter was about 20mm (its hard to be exact as it was behind the media panel back box). Can you identify whats inside the pipe from the colour and size then ?

I thought cables always go vertical from the socket (as well as plumbing), so I was surprised to see a horizontal pipe behind the media panel back box.
 
Hi freeflyer. I expect the media box has been 'chopped' into the insulation.

Re the plastic pipe, 20mm is typical of electrical conduit, but its also used for av cables like co-axil etc. Does it terminate inside a socket back box perhaps?. If you google 'safe zones for electrical wiring', you'll see one such zone is from faceplate to faceplate horizontally. Safes zones are a good idea, but not everyone knows about them!

If you post another pic or two, I might be able to identify (I'm an electrician by trade).
 
Thanks ufo550, I know there is some kind of breather membrane behind the media panel back box - you can see the silver membrane in the photo. Would that membrane be there because the insulation has been chopped into ?

At first I thought the plastic pipe was just protecting the cables going into the media panel (which has cable for mains, ethernet, telephone, tv aerial and sky), but it doesn't.

I removed 4 screws which are holding the backplate to a metal frame mounted in the wall, but I was unable to remove the backplate. I don't know whats preventing the backplate from coming out. Could there be some plaster or adhesive stopping it ? Or is it just the cables stopping it, which enter the top of the backplate through some rubber grommets ? A picture of the backplate without the yellow pipe highlighted is below...

IMG_5608.JPG


I've come across these 'safe zones' before, but do they still apply to low voltage cable such as speaker cable ?
 
Just be careful taking the faceplates off without the circuit being disconnected first. You need to follow safe isolation, very important.

Low voltage is defined as (UK) as 50–1000 V AC (DC other), so no speaker cables do not apply, but it would make sense to install them in similar zones to prevent damage (which wont be the case going around your door frame).

Re the plastic conduit, just note its position and now be aware it's located in a 'safe zone' when you do your work.

Can't tell from that photo whether that's a membrane or the silver foil of celotex/kingspan, but if the back box is 70mm deep, is gonna be past the plasterboard and into the range of the insulation, I would of thought.

Be careful with what your are doing re those faceplates.
 
Thanks ufo550, don't worry, if I were to try and remove the back box I would disconnect the circuit (I'm qualified with an HNC Electrical Engineering and Electronics degree). I might not bother removing it though because I doubt it will tell me much, other than confirm that the insulation has been chopped.

Im fairly sure it is a membrane behind the back box, when I tap it I can see it move like a membrane. I can also see the silver foil on the insulation blocks where I made the two holes (which I accidentally pierced and drilled into the insulation!). I often see these Kingspan insulation blocks where there is building work in progress on site. I think they must also be covered with a Protect insulation breather (note that this picture is of a block of flats)...

FullSizeRender.jpg


But as there appears to only be a 9mm void on the external wall (other than where the media panel is located), I think it will be difficult or impossible to route cables behind the plaster board. I was hoping there would be a 25mm void and planned to drill holes in the studding to pass the cable through.

It sounds like the only other option I have is to remove the skirting board and try and hide the cable behind that somehow. But then I still have the banana socket wall plates to fit in each corner, so I will still need to channel some plaster board and from the sounds of it I will need to chop the insulation (like the media panel) because the back box of these banana socket wall plates are 47mm deep.

And there I was, thinking it wouldn't be too difficult to hide these cables :-/

The sales office of the development site suggested I contact customer services about obtaining blue prints for the house, although I am sceptic they will be willing to provide these and even if they would be willing, I bet they would want a lot of money for them.
 
freeflyer
if you go with the rebated skirting board option you may not need to go over the door frame it may be possible to go under the door tread plate if you have one.
but from looking over the options i would also recommend flat cable under the carpet it may be a lot less hassle and cheaper to get i fitter in to refit it if you get it wrong.
 
I've made a break through (and a mess) !

I've cut a section of plaster board where I originally drilled the two holes and can now see whats going on.

The insulation block is only at the bottom of the wall, ~90mm above the top of the skirting board / ~180mm from the floor. Then the insulation block finishes and there is the silver breather membrane (which is the same membrane behind the media panel back box). The depth is ~60mm from the face of the plaster board to the the silver breather membrane...

IMG_5627.JPG


IMG_5628.JPG


So I just need to make sure that I make holes in the plaster board higher than the insulation block at the bottom.

Come to think of it, I should make the cable routing directly horizontal from the media panel (i.e. 'safe zones'). But then I remembered the plastic pipe I found behind the media panel, so I would need to be careful not to cut through the pipe, especially as I dont know whats in it.

So do I route the speaker cable horizontally above the insulation block but below the media panel ?

Or should I attempt to remove the media panel back box to further investigate the plastic pipe ?

Should I cut a rectangular hole (like in the picture) where every stud is and then fit new plaster board pieces which can be screwed into the studding ? There are 2 pieces of plaster board, 12.5mm thick.

Should I drill a hole in each stud to pass the wire through, or should I make a rebate in the front of the stud ? Will these studs be load bearing ?
 
PS. Any tips on positioning of the wall plates ? After searching on Google, am I right in saying that the sockets need to be mounted at least 350mm away from a corner and between 400mm to 1000mm high off the floor ? My existing sockets are ~450mm off the floor, but in two corners of the room where there are mains sockets fitted, one is ~300mm from the corner and another is ~260mm from the corner.
 
The height from floor is about being part m
compliant. You should keep the sockets at 450mm.

Usually quoted as being 350mm from the corner, but I don't think that is in regulations. I just think that's common sense so you aren't trying to install a back box near to the safe zone for wiring in the corner.

EDIT - I have just been through the Part M regs - the corners are mentioned as 350mm. So you should aim to follow that guidance (as your house would have been constructed to that standard).
 
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freeflyer, I would invest in a pencil, straight edge & pad saw for the next hole you cut! That way, you can re-instate the piece of plasterboard you have cut out.

The stud work is not load bearing in that sense, its there to create a wall and affix the plasterboard too. It would better to drill a hole rather than notching (notching is frowned upon for cables), but you would need angled drill to achieve that. Here is a useful document outlining DIY projects in a timber framed house;

http://norscotkits.co.uk/wp-content/uploads/2016/06/Living-In-A-Timber-Frame-House.pdf

Page 17 details drilling stud timbers.

Be careful when cutting the plasterboard, that you are just cutting the plasterboard, and not any concealed water pipes and cables (that have not be installed in safe zones!). And try not to damage the membrane & celotex.

I would leave the media panel and plastic pipe alone. It is difficult to tell from your pic, what the white pipe is. I see you stated it was 20mm in diameter, which is a typical size for electrical conduit. But such conduit is used for other purposes, such as running speaker cables! I would leave alone, just noting its location.

Safe zones are for low voltage cables. As far as I'm aware, they are not required for data or communication cables (but don't quote me on that). However it would make sense to run your speaker cables in said safe zones, to prevent damage to them. The idea of safe zones, are to prevent injury to persons from drilling into cables (low voltage) firstly, and secondly damage to cables from such actions.

Personally, if it was me, I would run the cables in a rebate behind your skirting as previously advised by others.

PS my references refer to Building Regs in England & Wales, and BS7671 UK Wiring Regs.
 
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Firstly I would just like to thank everyone for the replies.

I seem to be doing this all wrong :(

As I was expecting to have to cut a lot of holes in the plaster board (i.e. where every 600mm stud is located) I bought a circular saw thinking it would make the job easier...

Titan TTB689CSW 500W 85mm Mini Circular Saw 230-240V

But I've now found out that a circular saw is the worse tool for cutting plaster board, so I will have to take it back for a refund.

I originally used a plaster board hand saw for making the hole in the plaster board...

Stanley FatMax Jabsaw & Scabbard

But I struggled with the plaster board hand saw because I deliberately tried not to go through the 2 layers of plaster board with the saw. I wanted to avoid damaging the membrane and insulation, so I only did a shallow cut and then knocked the plasterboard out, but this was cumbersome and messy.

So I bought the circular saw because the depth can be set (up to 25mm). I thought I could use the depth setting so that it only cut the plaster board, thereby avoiding cutting anything behind the plaster board such as the membrane, insulation, cables or pipes.

Regarding the plastic pipe, I am now wondering if it is for the outside tap (see post below).

As for the alternative option of running the cables in a rebate behind the skirting board, is it the plaster board I rebate or the skirting board ? And what tool would I use to make the rebate ? Do I also rebate the architrave when going around the door frame ?
 
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Take that circular saw back for a refund, you'll do more harm than good. The Stanley pad saw is more than adequate for the task you have in mind.

Re the rebating, either or both of the plasterboard and skirting would work. As you have two depths of plasterboard removing one piece behind the skirting would give you a void of 12mm. A local builders supplier would also be able to supply a replacement skirting with the back rebated.

freeflyer, I'm getting the imprecision this project is beyond your capabilities - no offence - get someone in to do the work or use Wi-Fi :)
 
The plastic pipe could be water for your heating. Do you have a radiator nearby?
 
'They sent me this drawing and advised that I get a professional to do the work...' - Post No. 1 (and 22) may have had the solution!

Joe
 
OP, you want a Multi Cutter for this job. Circular saws are just too much for this job, and massively dangerous in the wrong hands as well. I have a cheap one, but have yet to get the confidence to give it a go. Just too easy for me to do harm with it.

Use something like this:

Draper 23038 250W 230V Oscillating Multi-Tool Kit: Amazon.co.uk: DIY & Tools


The job you are doing is not *hard* but it is *tricky*. For just speaker cable I would simply go down the route of buying 'D Conduit', linked below.

D-Line Mini Decorative Trunking White 30 x 15mm x 2m Pack of 6

The amount of mess you will make rebating the plasterboard is not worth it. The below sits on your skirting board and I guarantee it, no one will notice it is there. I would use this to go up & over the door frame, and down the other side as well. You can get ''corner'' sections to it so it is neat & tidy. I have a 50mm(!!) ducting running down one side of my room to hide several cables in. I havn't even bothered painting/filling around it as it is pretty discrete as is.

You can then either use this ducting to go up the wall to the speaker, and use ''Decorators Caulk'' to fill the gaps and paint it, OR use the multi cutter & small chisel/Stanley knife to take out a small channel in the plasterboard for the speaker cable, then fill & paint over it. You *will* see where the wall has been cut & re-painted over though, so make sure you are happy to live with that compromise.

Failing that, take a small crowbar & pull off the skirting board, and run the speaker wires behind it, before gluing it back on/gluing on a new skirting board. You do risk damaging the plasterboard wall though.
 
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