The Secretary, for the purposes of this subchapter, shall have the power to determine and prescribe the standards of adequate farm housing and other buildings, by farms or localities, taking into consideration, among other factors, the type of housing which will provide decent, safe, and sanitary dwelling for the needs of the family using the housing, the type and character of the farming operations to be conducted, and the size and earning capacity of the land. The Secretary shall approve a residential building as meeting such standards if the building is constructed in accordance with (1) the minimum standards prescribed by the Secretary, (2) the minimum property standards prescribed by the Secretary of Housing and Urban Development for mortgages insured under title II of the National Housing Act [12 U.S.C. 1707 et seq.], (3) the standards contained in any of the voluntary national model building codes, or (4) in the case of manufactured housing, the standards referred to in section 1472(e) of this title. To the maximum extent feasible, the Secretary shall promote the use of energy saving techniques through standards established by such Secretary for newly constructed residential housing assisted under this subchapter. Such standards shall, insofar as is practicable, be consistent with the standards established pursuant to section 526 of the National Housing Act [12 U.S.C. 1735f–4] and shall incorporate the energy performance requirements developed pursuant to such section.