Safe to run cables through wall?

[bobiscuit]

I'm going to mount a TV on a stud wall in a new-build house.

My plan was to run the cables from a hole in the plasterboard behind the TV, to a hole near the floor behind the TV unit, both covered with brushed faceplates.

But I saw a couple of places online say I shouldn't run cables through the wall cavity as there's a fire risk with the insulation... I'm no electrician so I'd rather err on the side of safety, but I've never heard of a central section of a cable spontaneously combusting??

There are 4 cables: 1 power cable for TV, 1 power cable for IKEA LED light strips, 2 HDMI.

I thought all the electric cables in the house already ran through the walls.... So is it genuinely a bad idea to go ahead with my plan?

 

[flameport]

Not an issue at all. Just make sure the wall plates and concealed cables are all in a vertical line.

If cables are surrounded or covered in insulation, they may overheat - but only if they are carrying a significant current. Those for a television are not.

 

[ban-all-sheds]

Firstly, is there actually insulation in that wall?

If there is I think the biggest problem you'll have will be in getting the cables through it - were you hoping to drop them down from behind the TV to the hole near the floor? Even if there's no insulation, are there no noggins in the way?

Cables can be run through insulation quite safely as long as the thermal effects of the insulation are allowed for when sizing the cables, so don't worry about your existing ones, and the ones for the TV and lights can be replaced if they aren't large enough. So what size are they (cross-sectional area of the conductors in sq mm is what we need to know), and how much current do the TV and the lights draw?

 

[ban-all-sheds]

PS

stud wall

You have my sympathy.

 

[Risteard]

There is also a risk of damaging cables pulling them through the cavity which would not be apparent.

Frankly it is a very poor practice.

 

[Echo the husky]

There is also a risk of damaging cables pulling them through the cavity which would not be apparent.

Frankly it is a very poor practice.

I thought it was a stud wall not an exterior wall cavity?

 

[Risteard]

There is also a risk of damaging cables pulling them through the cavity which would not be apparent.

Frankly it is a very poor practice.

I thought it was a stud wall not an exterior wall cavity?

Oh sorry, when I saw cavity I presumed we weren't talking about a stud wall!

 

[bobiscuit]

Thanks for the replies

Yes it's an internal stud wall. We considered mounting it on an external block wall, but the dot & dab adhesive is all over the place and we couldn't get a straight line down to run the cables. I don't fancy tearing the wall apart as it'll turn this into a much bigger job.

There is fibreglass type insulation in the wall (I think that's what it is... it's the "fluffy" kind!) and there will probably be noggins in the way. Do they take up the full width of the wall? I was hoping I could navigate the cables in front/behind them.

 

[ban-all-sheds]

there will probably be noggins in the way. Do they take up the full width of the wall?

Full width? No, but they will take up the full width between whichever studs you want to run the cables between.

I was hoping I could navigate the cables in front/behind them.

?

Probably.

Expect to have to cut holes in the plasterboard to get cables through or over noggins....

 

[DetlefSchmitz]

Do they take up the full width of the wall? I was hoping I could navigate the cables in front/behind them.

Assuming you mean the full 'thickness' of the wall, they are usually made using the same material as the studs so are the full thickness.

 

[Iggifer]

Yeah the noggin will more than likely fill the wall.

Best bet is to cut your bottom/top holes out first. Poke a stick etc down the stud until you hit the noggin, measure how far down/up it is then cut out enough plasterboard out in a tidy square above/below the noggin to drill a hole (repeat if unlucky enough to have multiple noggins) then patch up the hole afterwards

 

[winston1]

There are 4 cables: 1 power cable for TV, 1 power cable for IKEA LED light strips, 2 HDMI.

What about an aerial cable?

 

[bobiscuit]

There are 4 cables: 1 power cable for TV, 1 power cable for IKEA LED light strips, 2 HDMI.

What about an aerial cable?

Don't have one. We only ever watch things through netflix/chromecast and other online services. We live in a really bad area for TV signal (although good internet speed) - I'm sure an aerial high up on the roof would be fine but we've lived happily without it for 2 years so there's no point.

 

[winston1]

There are 4 cables: 1 power cable for TV, 1 power cable for IKEA LED light strips, 2 HDMI.

What about an aerial cable?

Don't have one. We only ever watch things through netflix/chromecast and other online services. We live in a really bad area for TV signal (although good internet speed) - I'm sure an aerial high up on the roof would be fine but we've lived happily without it for 2 years so there's no point.

I find it difficult to believe that a major conurbation like Glasgow has a really bad area for TV signal. But it's your choice of course.

 

[bobiscuit]

Regarding the TV signal, we're not in the city, we're on the outskirts surrounded by hills. No mobile signal in the house, no DAB radio, and poor TV signal (unless mounting high up on a pole) - but there's a nice view and the broadband speed is decent so I'm not complaining

Mounting the TV threw a couple of unexpected things at me... For one, I didn't realise most TV brackets are made for American stud walls where the studs are closer together, so the one I bought was wrong. I found this one which covers 60cm studs: http://www.amazon.co.uk/Cheetah-Mounts-APTMM2B-including-black/dp/B0012S4APK

Then it was a PITA finding the centre of the studs. I used a pin to "probe" for the edges, but one stud was 3 inches wide with a hole in the middle, and the other was 1.5 inches wide .
Turns out that because it's a wall that backs onto stairs, they reinforced parts of it by doubling the studs. So the 3 inch one was actually two normal ones, and I had to find the centre of one of them so I wouldn't go in-between.

And then of course there was a noggin half way down the wall which was very fun to deal with .

And only then I realised that I would need to replace all of my cables with longer ones! I had previously bought short ones to keep it tidy.

Took so much longer than expected that I ran out of time at the weekend. Will have to finish and paper the wall next weekend. Progress pic attached.