Many contractors are baffled
when it comes to choosing
the right concrete or
masonry anchor. With so many products
on the market and a lack of
easy-to-use performance data, a lot
of builders cling to the old standbys
— even when they're not the best
choice.
Concrete and masonry fasteners
fall into three broad categories:
mechanical, powder-actuated, and
chemical. Each type has its strengths
and weaknesses, and certain applications
where it excels.
The mechanical types all rely on
the same working principle: When
the anchor is struck with a hammer
or tightened down with a screwdriver
or wrench, it expands inside the
hole, compressing against the concrete
or masonry around it.
Early-day anchors were typically
made of lead and zinc — malleable
metals that