Mounting a TV on concrete or block

Concrete is the wall type people worry about most and, once it's drilled correctly, the one that worries us least. Nothing in a house holds an anchor better than poured concrete. The catch is that "concrete wall" can mean two very different things.

Poured concrete vs. concrete block

Poured concrete is solid all the way through — basement walls and some condo buildings. An anchor anywhere in it is strong.

Concrete block (cinder block, CMU) is hollow inside, with solid webs between the cells. Garages and basements in Alabama are often block. An anchor in a web is solid; an anchor in a hollow cell needs a different design.

A quick test hole tells you which you have: the drill either keeps meeting resistance or suddenly breaks through into a void.

The right drill and bits

A hammer drill (or better, a rotary hammer) with a carbide masonry bit sized exactly to the anchor. A regular drill will polish the surface and overheat. Blow or vacuum the dust out of each hole — anchors grip the wall, not the dust.

Anchors that suit a TV

• Sleeve anchors and wedge anchors for solid concrete. They expand as you tighten and are rated in hundreds of pounds each.
• Concrete screws (the blue ones) are fine for lighter TVs in good concrete when the hole size is exact.
• Toggle-style anchors or sleeve anchors long enough to bridge the cell for hollow block.

Plastic expansion plugs are for pictures, not for a 60-pound screen on an arm.

Painted, furred or covered concrete

Finished basements often have drywall over furring strips or a framed wall in front of the concrete. Then the choice is to anchor into the framing, or to go through the drywall into the concrete with longer anchors and spacers so the bracket doesn't crush the drywall.

What about the wires?

Power can't be buried in solid concrete after the fact. The clean options are a paintable cord cover ($39 with us), a cabinet directly under the TV, or surface conduit in a garage or shop.

Dust

Hammer-drilling concrete makes fine grey dust. We hold a vacuum at the bit and cover anything below. If you do it yourself, do the same and wear eye protection.

Concrete mounting adds $40 to normal labor with us — that covers the hammer-drilling, anchors and extra time.