Which of the following aspects is NOT relevant to restroom construction standards?

In the context of restroom construction standards, tile choice for the restroom is often influenced by aesthetic preferences rather than strict building codes or standards. While certain materials may be recommended for moisture resistance or ease of cleaning, the actual choice of tile is generally more related to design and personal choice of the client or the architect, rather than a regulatory standard.

Restroom construction standards do emphasize other elements like accessibility, fixture types (which must comply with plumbing codes), and the modification of existing finish systems to ensure safety and functionality, particularly in terms of ADA compliance and hygiene. These aspects are critical in meeting both health and safety requirements and ensuring the restroom serves its intended purpose effectively. Thus, while tile selection is important to the overall design and can impact the usability and maintenance of the restroom, it does not weigh as heavily in the construction standards compared to the other elements mentioned.