mounting to block wall
mounting to block wall
(OP)
I need some ideas on how to mount a flat screen TV on a mounting arm to a CMU block wall. The wall has firring and drywall. The TV weighs at least 75 pounds. What would be the best type of anchor?






RE: mounting to block wall
I anchored my flat screen arm to wood studs, but still designed the connection, because I don't believe for a second that the arm manufacturer had an engineer design the actual connection to the wall given all of the possible arm positions.
Check out Hilti's catalog and do the design checks.
RE: mounting to block wall
RE: mounting to block wall
RE: mounting to block wall
RE: mounting to block wall
RE: mounting to block wall
RE: mounting to block wall
jike (Structural)
8 Sep 09 12:20
If the block wall has furring and drywall, don't you need to mount to the drywall, not the block wall? How wide is the furring space between the back of the drywall and front of the block?
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To the contrary, actually. IF you mount to the drywall, you're concentrating all of the load (shear and pullout) from the entire load into a very few single point resistance points (the screws going into the drywall from the mount), THEN across the very weak drywall into the very few and extremely weak drywall screws into the furring strips, THEN down the very weak and extremely flexible furring strips, THEN through the very weak and easy-to-ripout screws holding the furring strips onto the block wall, THEN through the block wall to (something) that is (maybe) strong enough to hold drywall from falling off the wall.
Normal furring strip is 1x2 wood (cut at 1-3/4 x 3/4) or 1x4 wood (cut 3-1/2 x 3/4). Sometimes (not often!) a 2x4 is used, but very seldom.
Nope.
Best way is to go THROUGH the drywall at the points where the furring strips and firmly clamp the mounting hardware (the steel strips or mounting column) THROUGH the drywall and furring strip and block into the hollow center of the block wall.
3x or 4x 5/16" or 3/8" toggle bolts will do, or the newer epoxy-in long bolts that seat in both near-side and far-side of the hollow blocks with a flexible "screen" (or bag) that retains the pumped-in epoxy. 4x or 5x 1/4 toggle bolts will probably also work. The lowest toggle bolt resists shear, the reaming resist prying forces when somebody pulls down the TV.
The "bag" bulges out as the epoxy fills it, then as the resin hardens, the resin in the hole itself, the resin around the bolt, and the resin bulging in the hollow of the block wall all retain the bolt from being pulled out.
RE: mounting to block wall
RE: mounting to block wall
The bracket is bolted through a 2-foot high by 4-foot wide piece of 3/4" plywood.
The bolts appear to extend through the plywood, through the drywall, and into the studs in the wall, as they are on 16" centers. The bolts looked like 1/2" diameter, and they were spaced four vertically in each stud, spaced about 4 to 5 inches.
Each TV had 12 bolts holding it up, four high by three wide.
They seem pretty sturdy. The brackets weigh as much as the TVs.