Concrete Block Arches Circles

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Build concrete core filled masonry block arches without a template See also: Masonry Arch Header Cut and Placement Calculator

When the wall is core filled, the membrane (flashing) around the arch line stops the concrete. Remove off-cuts and extra blocks to reveal the arch.

Width
Height	In
Color

Cut all the blocks before construction. The cut blocks (all halves) that form the arch are numbered sequentially, with off-cuts numbered identically. Take the opening to spring height, then using a standard horizontal head support, go across the head, laying each cut in its place, its matching off-cut on top, with a membrane (aluminum flashing is ideal) between the two. Lay the cut, place the flashing on top of the cut line and lay the off-cut to lock membrane in place.
Use overlapping lengths of thick, strong (aluminum) flashing about 3 feet long so the flashing doesn't get in your way.

An arch has 2 identical sets of cuts
(left and right sides). A bulls-eye (circle) has 4.

Scale

You can easily combine this Template-less Arch System with the Circular Wall System to build circular walls with arches.
Neither system requires a string line, so they combine easily.

You can also use the Gable Cutting System to build arches or bulls-eyes in your circular raking wall. If you'd like more detailed info, please Contact Us

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Don't cut it, or cut it wet so there's NO DUST - Silicosis Sucks
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How should we spell it?	Metre Meter
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