As-built drawing is useful.
For you as owner, it’s essential to have a complete set of as-built drawing. from all involved suppliers.
An as-built drawing is a revised drawing made by a contractor after his construction work is finished.
The as-built drawings should contain any changes made from the initial drawings and it should include a mutual written agreement if there has been major changes under the construction work
The complete set of as-built drawings shall provide an exact rendering of the entire project, such as the position of the road, supply line, drains, buildings and the installed equipment when the work is completed
Since as-built drawings contain records of all installations, they are helpful if you as an owner decides to modify the building in the future, or if problems arise that you as the owner needs to troubleshoot upon completion.