Rebar

Using rebar in VOBB construction is simple, but proper planning needs to be made in advance of pouring in the concrete. The following suggestions/comments are based on questions we have received in regards to using VOBB:

1. Rebar "Should NOT" be continuous as it is too much work to raise the VOBB blocks over the rebar which is very wall height. We recommend that the rebar be placed in the "wet" foundation one foot on the external walls and sticking out two feet vertically. It will probably be easier to drill the hole for there rebar for the interior walls.

Please see picture of commercial job:
Rebar in the foundation makes the VOBB block wall have super strength

For a residential job of where a worker is drilling a hole to insert the rebar:
Drilling out a 1/2 inch hole with a hammer jack to insert the vertical rebar.

For residential job where rebar was placed when the foundation was wet:
the slab was poured with rebar on a four ft. spacing and the rebar two feet high to insert in the VOBB

For rebar for a duplex:
One row of VOBB block is placed for all walls to be sure of the measurements.

2. We do NOT tie the rebar.  Labor to tie rebar is expensive.  Rebar costs about 10 to 12 cents per foot.  We recommend to overlap the rebar (just stick the rebar in when the grout is wet for the "next" layer).

3. We do not splice the J-bolts together with the rebar.  We recommend the J-Bolt be 18" Long so that it can grab three VOBB's.  When you put the bolt on to tie down the top plate, this J-bolt then post-tensions the three top VOBB
together which makes the top very, very secured.

4. We do not have any recommendation on epoxy.  We have only had one job where epoxy has been used. On one job, the contractor drilled the hole with a half-inch jack hammer drill.  The rebar then had to be hammered into the hole as it was a tight fit.

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One job we liked, is where they filled all cells of the VOBB block on the first row. Please see:

Please note: Do NOT fill the cell to the top unless it is the top row. If you fill it to the top, the next course will not be anchored as well to the VOBB below. See picture above.

Also note: We recommend on the very corner, to fill the corner and the two sides.  As such, if you then mark off four feet spacing for the rebar in the foundation, you should start from the side cavity, not the corner. This makes
a difference of six inches, but is very critical where the rebar goes if you fill every other cell.

Also note: We like to dry-stack the VOBB block without lifting the VOBB block over the rebar very much. As such, the rebar then gets "hidden". You may want to use spray paint to make sure you do not get off in which cell is to be poured. Believe it, we have seen people who can not follow a straight line and they then end up pouring the grout in the wrong block cavity.

Before the concrete is poured:
See the markings on the form-board for where to stab the rebar on a vertical basis. .

REBAR ON A HORIZONTAL BASIS
Some projects my require rebar to be on a horizontal basis. As such, a notch can be cut in the top or a hole can be drilled and the rebar inserted.

WITH A NOTCH CUT IN THE TOP

VOBB to be used over a doorway/window

WITH A HOLE DRILLED TO USE IN A LINTEL/HEADER

The drill to drill the holes in the VOBB block. If the rebar is 1/2", then the bit should be one inch

   one inch hole for the rebar is drilled on a horizontal basis to make a lintel

  rebar inside a one inch horizontal hole for lintel

WITH A "V" CUT IN THE TOP