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Do I need steel beams for a very short block wall (there is an existing poured cement wall and we wish to raise it by about a foot or two) to raise the height of the wall around the stairs. On top of this will be a wooden handrail.

The reason I ask is because I see the contractor has done the bricks together with cement but no steel beams (rebar). Is this secure or will it eventually topple over?

TIA

  • Hello, and welcome to Stack Exchange. The handrail is the key; if someone whacks sideways against it, will it break the additional wall? The rail uprights need to be anchored well, however that is to happen. – Daniel Griscom Dec 25 '16 at 16:05
  • Thank you! I'm not sure if this makes it better or worse, the handrail is not the sticking out kind, but rather wood to be placed on top of the cement blocks. – KITHP Dec 25 '16 at 19:49
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Yes, you should add rebar across the joint between to old and new block wall. Do this by using a masonry drill (preferably a hammer drill) and drill 3-6" vertically down into the existing block wall top where the hole / rebar dowel will not be in the way of adding the next row of block. Best to use 1/2" or #4 rebar for this purpose and use the same size masonry drill bit to do your drilling. It's best to get the block cut and placed into position before you do the drilling to be sure there's no placement conflict between the intended new block layer and the rebar dowel holes to be drilled. Once you have them laid out on the wall then you can mark the hole's placement. I'd use a dowel in each corner hole and at least every other hole in the new block's run. Cut your rebar dowel length the depth of the drilled hole plus the block layer height minus 1-2" so they don't stick out of the new walls top. Fully insert the dowel into the drilled hole by hammering the rebar into the hole with a 2-3# mallet until they hit then end of the drilled hole.

*Rebar is meant to provide stability for the rigid concrete matrix or material. The reason you see rebar in bridges is that while the concrete provides a platform to drive on it's very rigid and will break apart if stressed past it's physical abilities. The rebar in the bridge keeps the concrete or matrix or material together and aligned in case of cracks in the concrete and strengthens the overall concrete structure with much less steel than in a conventional steel only bridge structure.

  • Thank you for the most helpful and detailed explanation! For a dowel do I use just a small portion of Rebar and then tie them together, or just sick the whole rebar into the hole or what? Also I'm really glad bridges are built this way, but do you think it's likely that 2-3 rows of blocks on a stairs (on a wall which is a bit low) is likely to fall over over time? Thank you so much! – KITHP Dec 25 '16 at 20:35
  • unfortunately it does not let me upvote you as I am new :( – KITHP Dec 25 '16 at 21:35

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