Mount TV on odd (to me) chimney breast.

[KiloBravo]

Complete DIY simpleton here (but I'm trying!), so please bear with me...

I want to put a TV on the chimney breast but I can't work out how to mount it. I know I should try to attach it to a stud (if it exists). It looks to me like a false wall that's been put in place around the actual chimney breast. Tried finding studs but I'm not sure there are any (tried magnets, no joy). By a lot of knocking I think I've found where the solid elements are, but no idea what type of wall this is and if they're actually studs.

Versus all the pictures I've seen online of other people doing the same, this wall seems weird. I've attached a pic, the red lines highlight where the walls seems solid. Funnily enough, the empty space right there in the middle, is exactly where I want to put the TV, but it seems completely hollow there.

Any guidance on how best I should approach this would be very much appreciated.

 

[Lucid]

These threads should give you all the answers you need:

Mount TV to plasterboard | DIYnot Forums

Issues Wall Mounting TV | DIYnot Forums

How to fix bracket to wall without drilling through cables | DIYnot Forums

Wiring surround speakers in a new build | DIYnot Forums

Whether the thread is about mounting a TV bracket or speaker brackets makes no difference. It's all about dealing with walls, which is the essence of what you're asking.

 

[KiloBravo]

Thanks lucid. Having looked through the links (particularly the firstl) I'm almost certain it's dot and dab and explains why I couldn't find any studs.

When I used the magnets though, there seems to be metal strips going along the edges of the chimney wall and around fireplace space at the bottom, what's that for?

Would I be right in saying that using the corefix fixings is pretty much a safe option no matter what sort of false wall it is? As in it'll either be overkill or just right.

 

[ericmark]

In my last house the distance between finished plaster and the chimney void was about three inches, this house much thicker more like eight inches, so one does need to be careful not to actually drill through to the actual flue.

It was standard practice to use metal corners to assist with plastering, catching this thin reinforcement can cause problems, in the main you can get some pointers of type of flue due to age of house, the flue brick was popular in the 80's mainly for gas fires, before that flues were designed for solid fuel and were a lot thicker, so how much the chimney breast comes into the room is a good indication.

 

[Mottie]

When I used the magnets though, there seems to be metal strips going along the edges of the chimney wall and around fireplace space at the bottom, what's that for?

Angle beading to get a straight edge/finish.

 

[Lucid]

Thanks lucid. Having looked through the links (particularly the firstl) I'm almost certain it's dot and dab and explains why I couldn't find any studs.

When I used the magnets though, there seems to be metal strips going along the edges of the chimney wall and around fireplace space at the bottom, what's that for?

Would I be right in saying that using the corefix fixings is pretty much a safe option no matter what sort of false wall it is? As in it'll either be overkill or just right.

BIB: They're metal edging strips. They give a harder-wearing finish to the external corners than a simple board edge only. If you think about it then that makes sense. Plasterboard is a bit like a chalk and paper sandwich. The edges are the weak spot, especially an external corner which is more likely to get a dink or knock at some point in its life.

Corefix, Rigifix and similar all work on the same principle; there's a plastic-plug-type fixing but with a metal core to act as a bridge across the cavity. This transfers the weight to the wall proper rather than the weaker boarded surface. As such, the strength of the fixing depends on how well it is embedded and anchored in to the block or brickwork that forms the chimney breast.

Once you've got some experience of drilling in to walls you'll start to learn the difference between hitting brick (relatively hard) and hitting the mortar (relatively soft) between them. You may even encounter the situation where the drill bit hits the edge of a brick and then "walks" sideways as the bit head slips off the brick and in to the mortar joint. That'll leave you with a nice oval hole

Hitting mortar may still give you a decent anchoring point, or if the house is very old - say Victorian era or earlier - then the mortar could fracture around the hole. This is why you start with a smaller diameter drill bit to make a pilot hole to the depth you need, then drill in again with a larger diameter bit to the actual size you need to make a snug fit for the plugs you're using. You're trying to avoid the situation where the plug rattles around loose in the hole. A fixing where the plug just spins as you try to tighten it might as well not be used for all the good it will do. The tip then is to make sure each hole and the fixing that goes in to it counts for something.

Keep in mind too that the average 58-65" TV doesn't weigh more than 30kg, and just one of these heavy duty fixings will handle almost that weight alone, so by the time you have four or six with solid anchorage in to the wall then you've got the weight more than covered by a multiple 3:1 up to 5:1 for a simple hang-on wall bracket. The maths changes a bit though if you're using a full-motion pivoting wall bracket.

 

[KiloBravo]

Thanks for the information all. That's given me a good starting place for what needs to be done.

I went and drilled a tiny hole in the centre of where the fixings would be going for the TV mount. It seems like the plaster goes all the way back to the harder surface behind it, so there's about 3.5cm of plaster and then hard wall (no air gap). Is this heard of? or maybe I've just drilled through the 'dot' part of the dot and dab? I guess it doesn't really matter so long as the corefix fixing goes through the plaster and into the hard wall?

Also, as it's 3-3.5cm, should I be worried about the fact that 7-7.5cm of the rest of the corefix fixing will be going into the wall behind it? I don't know how thick that hard surface is, what if it goes right through that hard wall? or is 7.5cm to narrow for any sort of hard wall and so I'm worrying about nothing?

Also, was looking to get something like this: Invision TV Wall Bracket Mount for 26-42 Inch Screens: Amazon.co.uk: Electronics .... in case that makes a difference.

 

[Lucid]

Yeah you've hit a blob of the board adhesive. IME it's harder than plaster, but not as hard as brick. Your mileage may vary.

You can Google the dimensions for a standard British house brick, or walk outside and look at an external corner joint where the long and short sides ogmf bricks are both visible if you prefer something more visual.To save you time though, the front-to-back thickness of a brick is a shade over 10cm.

This is your first go at doing a TV wall bracket. You've chosen a pivoting bracket. I would recommend you look at a different design; a bracket with a larger wall plate. You'll have a bigger safety margin with four or six widely spaced fixings rather than relying on two or three in a vertical array to try to withstand the twisting force as the TV is moved.

 

[KiloBravo]

Thanks again Lucid.

Ok, sounds like I'll be fine with corefix then regardless of what I find back there. (thanks for saving me the time )

I did wonder about my choice of tv mount, glad i posted it now. Thinking of this instead: Invision Ultra Strong TV Wall Bracket Mount Double Arm: Amazon.co.uk: Electronics ...is this the sort of mount you mean? think it's 4-6 screws from what the information says.

On the cabling, originally as i thought it was a stud wall, i was going to attempt to put the cabling behind the plaster and pop it out into the old fireplace space where a tv unit would live. As I've discovered its dot and dab, that option seems like a no goer. Is there another way of achieving this that I'm not thinking of or would any method require a fair bit more work (i.e. plastering/painting etc)? Am i stuck with external trunking?

 

[Lucid]

Is the fireplace real or just decorative? By real I mean useable even if you yourself aren't using it.

BTW, never found the image you alluded to in your OP. That, and perhaps a shot or two up the chimney if it's a decorative set might help.

 

[KiloBravo]

I'm pretty certain there's a real chimney behind the plasterboard. It's been like this since I bought the place but I'm 99% sure.

I'm going to re-attempt attaching these images....

 

[Lucid]

Those pictures are useful. Thanks.

Surface thinking is a possibility and there's decorative trunking with a round profile called D-Line; but even so, you're still going to have to negotiate two 90-degree bends to get cabling going from inside the alcove of the fireplace aperture up to the TV. That would be okay with say a bit of speaker wire, but power cable, a HDMI lead and maybe an aerial coax too? That's going to be pushing it unless the trunking is a much bigger cross-section or you have multiple runs. That wouldn't be my first choice for aesthetics.

There's also the question of where you get power from for the gear that'll live in the alcove as well as the TV above it. Is there already a socket in there?

TBH, I think the best course of action for your as a DIY noobie is to to get a local multi-skill -property maintenance company or -AV installer in to chase in conduit big enough that you can run today's cable but also big enough to be able to pull through new cable should you need additional connections or standards change.

When I started installing professionally, SCART was the common standard and Component video was the high quality/HD cable of choice. In 2005 HDMI hit the UK. Within 5 years SCART was effectively redundant and Component was going the same way. Since then we've gone through four changes of HDMI cable specs. These are Standard Speed > High Speed > Certified Premium High Speed > Certified Ultra High Speed. We've also seen the widescale adoption of smart features and streaming, and we now have access to watch UHD 4K content and can game at that level too. Not everything is applicable to every TV users of course; The bigger point is that standards and facilities constantly evolve.

Trying to future-proof is a fools errand because we haven't a clear idea far enough ahead and in some cases the cabling required isn't yet available. Equally though, choosing to ignore the march of technology can leave a user frustrated. Smart TVs have a nasty habit of slowly getting dumber over time as the manufacturers forget their older sets so they no longer get updates or simply have hardware that's too slow. Changing an entire TV just to get iPlayer back working or to access Prime/Disney+/Netflix in 4K etc is a great way to flush cash down the drain when a £50 Firestick will do all this and more. But it needs a direct connection to the TV or an AV receiver and it needs more power than a typical TV USB socket might be able to supply. Therefore you need some extra power sockets behind the TV, and because the wallwart PSU is bigger than a UK mains plug, they need some space too. What happens if you want to add Sky or Virgin some time in the future, or just a Now TV box?

 

[KiloBravo]

Lucid, firstly, really grateful for depth and insight of your response, really appreciated and helps a lot.

In answer to your question, there aren't any power sockets in the fireplace area.

I do think you're right, I'm probably biting off more than i can chew with this mini project, assumed it would be easier than it appears to be. So i think I will just get this done by a pro, if I can find someone reputable in my area!

Thanks for the additional information on the screen placement, funnily enough where you've placed it on the wall is pretty much where I've marked out to put it as thats roughly the right angle from a sofa.

I'm thinking that I may also use an interim solution of just putting it on the wall and using a cable sock sort of think to keep the cables bundled and somehow tack that into the fireplace space. There's a spare socket on the left hand side so with a small unit in the fireplace space I can just use a short extension cable to bring the power behind it and plug things in. Not a great look but it at least gets the job done whilst I search around...