I've had times where I've attempted to place an object only to be met with a red border preventing me from doing so, however, this red border seems to show at times where it appears an object shouldn't conflict with a previously placed object.
This issue has happened in games before; Cities: Skylines, and Fallout 4 are two of the obvious ones, but with mods that assist in fixing the issue.
Cities: Skylines has a mod called Anarchy that allows roads to be placed through buildings, trees to be placed on roads, and whatever else the user wants to do, no matter how unrealistic or wild it may seem, but users don't use it to be wild and unpredictable, they use it to create beautiful scenes that would otherwise be impossible in vanilla.
Fallout 4 has a myriad of issues regarding placement, so when a user became sick of it, they created the mod, "Place Anywhere" which prevents objects from appearing red at all, they can be placed anywhere and can be used to scrap anywhere as well (so long as the assets used are scrapable anyway).
Now Two Point Hospital also has the issues that these other two games face, and so it's only right that it too has a mod that allows the placement of objects anywhere, this way rooms can be designed to be more compact and made to look much nicer as a result.