21 GCA § 61142: Accessory Dwelling Units: Standards.

An ADU shall:

(a) share utilities with the main house, or utilities may be billed separately, by separate meter; provided, that the ADU complies with the standards set by the agencies responsible for utilities;

(b) be covered under the same homeowner’s insurance policy as the main home or separately, at the option of the homeowner;

(c) not be sold separate and apart from the primary single-family home;

(d) be subject to the following setback requirements:

(1) a minimum side and/or rear yard setback of four (4) feet;

(2) if an ADU involves conversion of an existing structure detached from the primary dwelling and which conforms to the requirements of § 61141(b)(1), the minimum side and rear yard setback shall be a minimum of four (4) feet;

(e) comply with any wastewater or environmental impact requirements in public laws, Guam Administrative Rules and Regulations, Guam law, and federal law; and

(f) maintain minimum front yard requirements required in 21 GCA, Chapter 61, § 61501 for an ADU located in a front yard or on the front one-half (½) acre of a lot.