No provision of this chapter or regulation adopted under authority of this chapter shall be interpreted to require that the owner of a single- or two-family dwelling shall be registered or hold a certificate of registration to personally perform work upon the premises. However, this exception shall not apply to any person holding himself or herself out to the public as a building contractor, builder or one engaged in any of the building trades for profit. All such work shall be performed by such owner with the assistance of no more than two paid workers whose employment on the particular job shall not constitute the full-time employment of the two paid workers. (Ord. 457. Passed 9-12-66)