In what situations might a post-installed anchor be preferred over a cast-in anchor?

A post-installed anchor is preferred over a cast-in anchor primarily in situations where retrofitting is necessary or in existing structures with limited access. This is because post-installed anchors provide flexibility in installation, allowing for anchoring in spaces where it is not feasible to pour concrete with cast-in anchors. For example, if a building is already constructed and there is a need to install additional support or equipment, using post-installed anchors can be an efficient solution without requiring significant disruption to the existing structure.

This option highlights the practical application of anchoring systems in real-world scenarios, such as renovation projects or adding new elements to already functioning buildings. The ability to install these anchors after the fact makes them invaluable in certain contexts where access to infrastructure is restricted, or modifications must be made without starting from scratch.

Considering the other choices, they do not align with the unique advantages offered by post-installed anchors in specific situations. While cost is a factor in construction, it is not the primary reason anchors are selected, and ease of use alone does not justify their application across all installations. Additionally, limiting their usage solely to new constructions overlooks the versatility and necessity of post-installed anchors in existing conditions.