How to mount a TV on a concrete condo wall

First, make sure it really is concrete

A Toronto condo can have three kinds of wall within a few metres of each other: poured concrete, drywall on light steel framing, and drywall laid over concrete. Each one takes different hardware, so guessing is the most expensive mistake in this job.

A few quick tests narrow it down. Knock along the wall with a knuckle: drywall over a cavity sounds hollow between framing members, while bare concrete sounds dead and solid everywhere. Run a strong magnet over the surface: on steel-stud walls it finds a line of screw heads every so often, and on concrete it finds nothing. If you are still unsure, drill one small pilot hole in a spot the TV will cover. Gypsum board gives way easily and leaves white powder; concrete stops an ordinary bit cold and leaves grey dust. Drywall glued or strapped onto concrete gives you white powder for the first centimetre or so and then grey, and that wall needs anchors long enough to pass through the board and reach full depth in the concrete behind it.

Then ask the building

Before anything is drilled, read your condominium’s rules and talk to the property manager. The Condominium Authority of Ontario explains that a corporation’s rules have to be reasonable and consistent with the Condominium Act, and in practice they often cover three things that matter here: the hours when noisy work is allowed, whether contractors must sign in and carry insurance, and whether owners may drill into concrete at all.

There is also the question of what you own. Depending on how your condominium’s declaration draws the unit boundaries, a concrete wall or column can be a common element rather than part of your unit. The Condominium Authority notes that most owner-proposed changes to common elements need board approval and a formal agreement under section 98 of the Condo Act. A few anchor holes for a TV are not a renovation, but the property manager is the person who can tell you whether your building treats them as one. Ceilings and floors are a separate matter: a slab can carry steel tendons, reinforcing bar and electrical conduit, so never drill into one without the building’s written permission.

If the building asks for a certificate of insurance from whoever does the work, get it to the concierge before the day. A visit refused at the front desk costs everyone time.

The tools the job needs

Concrete is drilled with a hammer drill or, better, a rotary hammer, using a masonry bit of the exact diameter the anchor’s instructions give. A regular drill-driver with a masonry bit will mostly polish the hole. Add a shop vacuum held under the bit, because concrete dust gets everywhere in a finished room, a level at least as wide as the mount’s wall plate, a pencil, a tape, and a second person for the lift.

Choosing anchors

Most TV mounts come with lag bolts for wood studs, and some also include anchors for concrete. Use what the mount’s instructions specify for a solid concrete wall, and check that each anchor is rated for the load, not just for the TV’s weight. The common choices are concrete screw anchors, which thread straight into a drilled hole, and expansion anchors such as sleeve or wedge anchors, which grip the sides of the hole as they are tightened. All of them depend on the hole being the right diameter and deep enough, and on keeping the distances from edges and from each other that the anchor maker sets out.

A full-motion arm deserves extra respect. When it is pulled out from the wall, the weight of the screen acts like a long lever on the top anchors. Spread the load across every hole the wall plate offers rather than the minimum.

If the bit hits steel

Somewhere inside a concrete wall there is reinforcing bar, and sometimes electrical conduit. When the bit suddenly stops advancing and starts to ring or spark, stop. Do not lean on it and do not switch to a bit that cuts metal. Pull out, fill the hole, and move the mounting position a few centimetres; most wall plates have enough slots to allow it. A handheld scanner can warn you about steel close to the surface before you start, but none is certain at depth, which is why the rule is simply to stop when you feel metal.

Laying out and hanging

Mark the centre of the screen first and work outward from it. For a living room a good starting height puts the middle of the screen at seated eye level, then adjust for the sofa and the room. Hold the wall plate at the mark, level it, and mark every hole through the plate. Drill, clean the dust out of each hole, set the anchors, and fix the plate, checking the level again before the last anchor is tightened. Attach the brackets to the back of the TV using the screws that match its VESA hole pattern, then lift the screen onto the plate with two people and lock it in.

Cables on a concrete wall

A concrete wall has no cavity, so there is nowhere inside it to run a cable. The tidy answer is a slim surface channel, painted to match the wall, from the bottom of the TV down to the stand or outlet below.

Power is where people get into trouble. The Electrical Safety Authority advises against using extension cords as long-term power sources: ongoing power needs permanent wiring and outlets, installed by a Licensed Electrical Contractor. Pushing a TV’s power cord or an extension cord into a wall is not a substitute. An outlet behind the screen is electrical work, which the ESA says only a Licensed Electrical Contractor may be hired to do; on concrete that often means surface-mounted conduit rather than wiring hidden in the wall.

A mounted TV is a safer TV

Health Canada warns that televisions, furniture and appliances can tip over and injure children. A TV fixed to the wall properly cannot tip. If yours stays on a stand instead, anchor the TV and the stand to the wall with tip-over restraints.

The job, start to finish

When to hand it over

Call someone when the TV is large or on a full-motion arm, when the wall turns out to be drywall over concrete, or when you would like the cables and a new outlet sorted in one visit. We mount TVs on concrete across Toronto, with a written flat-rate quote before anything is drilled.