Consider the analogy of medical professionals.  Nurses, doctors and surgeons are all qualified to address medical problems according to their level of training.  But just because a surgeon is more qualified than a nurse does not mean you would see a surgeon for every medical issue.  Similarly, an architect is qualified to design building projects of a type and scale for which a Draftsperson or Building Designer is not.  An example is buildings over 3 storey’s high.  Just as you see the medical practitioner appropriate to your injury or illness, depending on the nature of your brief, a Draftsperson or Building Designer may be more than adequate to design and document your project. 

An Architectural Draftsperson generally has the experience and training necessary to prepare the technical drawings for council approval and builder for a design prepared by someone else.  Their knowledge and skills relate to how a building is constructed and how to represent that graphically according to the conventions required in the building industry.  An experienced draftsperson may also have the design capabilities of a Building Designer.  Building Designers have completed study or have recognition for skills and knowledge demonstrated in the field of architectural design which qualifies them for membership of an association of Building Designers.  Membership of the Building Designer’s Association requires a commitment to professional conduct and development.  Visit the website of Australia’s Building Designer’s Association for more information (http://www.bdaa.com.au/).  As well as knowledge of building construction and drafting skills, a building designer is capable in areas such as site analysis, passive solar design, site responsive design, design for bushfire and accessibility requirements, multi-residential design (up to 3 storey’s) and design of small to medium commercial/industrial developments.  As with any profession, individuals develop their own area(s) of speciality.  It is therefore, worth discussing with Building Designers you are considering the type of work they have experience in.