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The wall is made of the larger clay hollow brick (the red ones that we have in Europe), there is masonry/cement/mortar (not sure which) for connecting and putty + paint over them.

So my TV mount (one of those colloquially known as a VESA mount) became loose on one end (4 screws, just 1 loose for now), so I need to fix it.

First I assume (I have not loosened the screws) there are plugs (like the fischer duopower) that are inside the holes and then a screw screws into them. First, can I reuse the plugs that are already there if I unscrew all the screws to fix the loose one, or will I need to put new ones? Second, do I need some kind of masonry epoxy/filler or I can just put a new plug and screw in?

I know this might depend on the issue, but please give me a few ways that the situation can turn into, so I know what awaits me before unscrewing all the other screws and starting the job.

I do have a hammer drill if needs be and a few bits, so if redrilling is needed, let me know what needs to be done precisely.

Thanks.

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  • FYI, VESA is a dimensional standard (an organization, really), not a device type.
    – isherwood
    Commented Jun 13 at 12:45
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    @isherwood The name VESA mount is actually used to refer to a specific type of device in some parts of the world (just like hoover and dremel are in others). Commented Jun 13 at 23:32
  • Yeah, I know. I get lectured all the time about my mention of the misuse of terms. I'm not really interested in that. I'm interested in clarity of communication, which the term did not convey to all readers.
    – isherwood
    Commented Jun 14 at 12:49

2 Answers 2

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What not to do:

enter image description here

When putting an anchor for a heavy load into hollow brick you really want the plug to grab into at least one inner wall. The plug in the picture is too short.

can I reuse the plugs

No, and if they're duopower, pulling them out will probably be difficult.

do I need some kind of masonry epoxy/filler or I can just put a new plug and screw in?

It depends.

You need to check the hole: if it is not clean and round, or chips broke off from the brick, then a new plug won't work. In this case you either need to re-drill a larger hole and use a larger plug, or use a chemical anchor.

Then check the depth of the inner partition wall in the brick, see if you can get a long enough plug to grab it. If you can't, use a chemical anchor of sufficient length, which is the best solution anyway.

enter image description here

You need to use the sleeve, otherwise the mortar will fall off into the brick holes. It should be the correct length (like the one on the bottom).

enter image description here

Another solution is the poor man's chemical anchor: drill a much bigger hole, fill it with plaster or mortar, wait for it to set, then drill and use a normal plug like 8-10mm Fischer SX.

I do have a hammer drill

To drill into hollow brick, don't use the hammer, otherwise it will take off chips at the back leaving only a thin edge for the anchor to grab. Just set it to drill, use a masonry bit, and grind.

Here's a random pic from the internet showing the difference: when using hammer mode, the brick explodes leaving almost no material on the edges of the hole for the fastener to grab on. From the outside it may look okay but from the other side the hole actually looks like a crater. Without the hammer it's cleaner, it makes a hole with straight edges leaving a lot more material, so it's much stronger.

enter image description here

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  • Thanks for the details! How do I know how many inner walls are in the hollow brick and where I am exactly before tightening? You mention that duopower is not easily removable, non re-usable, this video shows otherwise: youtube.com/watch?v=7IVzvubW7fk Is he just risking it here? Lastly, I've always thought that I need to use hammer drill mode on any bricks including the hollow ones in Europe! I do not however completely understand what you said here, it will take of chips off at the back of the brick? What do you mean exactly, also what do you mean by grinding?
    – appwizcpl
    Commented Jun 13 at 22:14
  • 1) Just remove the plug and poke inside the hole with a screwdriver to get an idea of the depth of the void an the next wall. Also you didn't mention the thickness of the brick, is it a partition wall like 5cm thick brick, or an outer wall like 20-30cm? 2) When you pull the plug out of the hole it it will be all scrunched up, not reusable. The plugs in the video are UX not duopower btw. 3) For the hammer I added a pic to the answer
    – bobflux
    Commented Jun 14 at 5:47
  • If you drill a new hole, @appwizcpl, you'll know when A) you're through one partition wall, and B) When you hit a new one: the drill will lurch forward on you. At each lurch, you can stop and measure depth. If you can't fit a tape measure in the hole, simple insert a small wooden dowel until it stops, make a mark at the outside edge of the brick, and measure from the end to the mark. That's how far it is to the next partition wall. If it's not deep enough, drill through that partition and measure to the next one.
    – FreeMan
    Commented Jun 14 at 12:47
  • @FreeMan the thing is, the apartment already had the mount before I came in, so whoever did the job is not me.
    – appwizcpl
    Commented Jun 14 at 16:35
  • You may need to drill new holes and move the mount a few inches (to avoid weakness from the old holes).
    – FreeMan
    Commented Jun 14 at 17:29
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Are you using "standard" concrete plugs (split-in-hal-with-ribs)? Start by unscrewing everything and snap a picture. It is possible someone used the standard concrete plugs, which are usually ok, unless they meet cavity, then they are not. You can check shop for plugs like "Fischer Fixings Nylon Rawlplug" which feature screw hole at end and consist of 4 loosely connected bands - they expand and twist in cavities, so they will catch on the outer brick layer.

If the anchor plugs sit tight in the wall, you do not need replace them - just screw the screw back in and they will hold.

BUT Check the screw lengths and compare them to wall thickness. If they are shorter than half wall thick, you will want something bigger. Impact drill will be useful, but go slowly when deepening the hole - you do not want the plaster flying off the opposite side of the wall. Also, compare the screws diameter to the mount holes in your vesa mount. If they are visibly smaller, upgrade to larger screw+anchor, you want the max holding power that fits in the vesa mount holes.

After you install the vesa mount (presumably a tv?) put at least double the expected weight on it. For tv, you could hang your weight on it, if you're on lighter side. You do not want your tv falling off, obviously.

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