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
