Hi guys,
These all seem like valid points. There are certainly some specialized uses of the plural form. eg the works of a clock or the phrase something is in the works. We can speak of ten works of art.
In the construction trade, you can use the terms as noted, eg Clerk of Works, the Schedule of Works. These terms seem more like titles to me. I wouldn't think you can speak of a Schedule of Ten Works. So, it doesn't seem to me like a truly countable noun, if you can't count it.
Best wishes, Clive