What feature is required in the installation of cleanouts regardless of the pipe size?

The requirement for vertical service space in the installation of cleanouts is essential because cleanouts need to be accessible for maintenance, inspection, and potential clearing of blockages. This vertical space allows for proper installation and facilitates the usage of augers or snakes to remove clogs effectively. It ensures that the cleanout is positioned in a way that plumbing professionals can easily reach it, regardless of the pipe's size. Adequate vertical space helps in preventing any obstruction that might impede the servicing of the cleanout, thus promoting effective plumbing maintenance.

While horizontal service space can also be beneficial in certain contexts, the vertical aspect is crucial for functionality and ease of access. The requirement for no special requirements or additional support does not address the importance of accessibility and maintainability, which is central to plumbing code compliance and best practices.