How to mount heavy TV to plastered over brick wall?

[adamliaw]

Hi all, I am seeking advices for mounting my 85 inch (46kg) TV with mount (15kg) to a plaster over brick wall. According to builder, bricks are 90mm wide with 10mm plasterboard and 5mm adhesive (dot and dab method). I have done some research and found "Corefix 100mm tv wall fixing with Reinforced Steel Core" specially design for plasterboard over blockwork, are there anything similar that I can use? The closest i can find is ramset ramplug. but without the reinforces steel core to prevent shear force acting on the screw. 

So, are 10 of Ramset 100mm Ultra-Long Hex Anchor RamPlug, 4 top,4 bottom, and 2 side of the mount sufficient?

[MikeTNZ]

Hi @adamliaw ,

Given the specifications of your fixings/fasteners, that should be ample for this sort of load.

However, I ask the question, have you checked the integrity of the bricks behind the plasterboard?

How old or new is the building that you are doing this work in?

It wouldn't be the first time where the bricks have degraded behind the plasterboard.

What I would do, is make a small incision through the plasterboard, that will be behind the TV (possibly where the cables will come out)

and check what condition the bricks are in BEFORE you start drilling 10 mm holes in them, with a hammer drill.

{Edit: if you can tap the brickwork with a punch and hammer not have them break, you should be all good to go,

I believe that these fixings (when fitted correctly) will hold 25kg, your best fixings should always be at the top, so you need to be careful when drilling the upppermost holes, the bottom ones are only to hold the bracket in place.}

I hope that this advice has been of some help to you, if you need further information, by all means let us know.

Cheers,

Mike T.

[adamliaw]

Hi Mike.

Thank you for your advices. I haven't had a chance to check the integrity of the bricks, but it was built in 2019 so I was assuming that the bricks are still good. 

I will check the condition of the bricks as you mentioned prior to drilling. Thank you.

How about the shear load acting on plasterboard from the screw? As there are 5mm of cavity in between plasterboard and brick, I am worried that the screw will induce shear force on the the plasterboard over time. Is this something I need to be worry? 

Cheers,

Adam

[MikeTNZ]

Hi @adamliaw,

Wait, your mount is 15 kg in weight?

That shouldn't intrinsically be a problem, if you have 4 fixing points at the top, you just need to make sure that none of them fixing points go into the mortar between the bricks.

A standard Australian brick is 230mm wide ( to the face) × 110mm deep × 76mm high, bargain on 12 mm wide grouting, depending on who built the wall.

[adamliaw]

 

Hi @MikeTNZ 

yes the mount itself is 15kg, the mount is 820mm wide, with 8 mounting holes on top and 8 bottom, equally spaced. it’s able to extend 550mm out, pretty much the reason why I’m worried about the pull out capacity on the top anchors as the tv will be extended out sometimes for viewing. The brick itself is 90mm wide (depth).

Noted on avoiding the mortars between bricks. Will try my best to avoid. 
thank you. 

{edit: sorry uploaded picture is one size bigger than mine, couldn’t find the sketch of my current mount, similar but small 600mm wide with 6 holes top and 6 bottom.}

[JacobZ]

Hi @adamliaw,

Thank you for your question about mounting a heavy TV to a plastered brick wall.

It's great to see @MikeTNZ has already jumped in to assist and his advice is excellent. As he's said, the main thing is ensuring you hit the brick, not the mortar as the mortar has no real holding power.

The only thing I'd consider changing is to use 80mm plugs like these Ramset 10 x 80mm Ultra-Long Hex Galvanised Anchor RamPlug as opposed to the 100mm. 

My reasoning is that if your bricks are 90mm deep, with 10mm of plaster and 5mm of adhesive, then a 100mm plug would only leave 5mm of brick behind the plug. There is a good chance that while using a percussive drilling method, this 5mm of material behind the plug will blow out. Reducing the depth of the plug by 20mm should give you a buffer to prevent this blowout.

Let me know what you think and if you have further questions, please don't hesitate to ask.

Jacob

[adamliaw]

Hi @JacobZ 

Perfect thank you! 

Also to @MikeTNZ  Thanks for your advices!! 

[MikeTNZ]

Hi @adamliaw,

No worries, good luck with this project.

Cheers.