Generally, "homeowners" constructing or improving their own residence or accessory structures may do the construction or repair work themselves. In most instances, any third party doing work for compensation at an existing or proposed residence must be licensed or registered. Upon completion of the work, the permittee must be the Owner/Occupant of the subject dwelling or property.
Generally, all non-residential (excepting Agricultural) and multi-family construction must be executed under the supervision of licensed contractors. In most cases, all construction related to a public occupancy or use must be executed under the supervision of licensed contractors.
Regardless of who is performing work, ALL WORK, including renovations, SHALL BE DONE IN ACCORDANCE WITH THE BUILDING CODE OF ALLEGANY COUNTY, MARYLAND
For guidance relative to the statements above, you are encouraged to review information at the following websites:
New Dwelling Units: Maryland Office of the Attorneys General
Home Improvement: Maryland Home Improvement Commission
Electrical work: Maryland State Board of Electricians
Plumbing work: Maryland State Board of Plumbers
General Codes (Maryland): Maryland Codes Administration