If an unregistered design is created in the course of someone’s employment then the design is owned by the employer by virtue of s214 CDPA 1988.
There have been a couple of interesting cases on this area:
Ultraframe (UK) Ltd v Clayton and Others Ultraframe (UK) Ltd v Fieldings and Others  EWHC 1964 (Ch),  ALL ER (D) 167 (Dec) in this case the company’s managing director and major shareholder created the design however the company itself was deemed to be the owner. In the case of A Fulton Co Ltd v Grant Barnett & Co Ltd  RPC 16 again the director created the unregistered design however in this case there was no service agreement between the director and the company, in the end though the company was still deemed to be the owner of the design.
What about where instead of being created in employment the design was commissioned?
If the design is created as a result of a commission then the commissioner owns the design (note the difference between this and copyright). Ou should however bear in mind that these rules can be contracted out of, so check (or in fact amend) your employment contracts etc.