13-200-230 Increase in one additional dwelling unit.

   In any residential building or building of mixed occupancy, with one of the occupancies being residential, the number of dwelling units may be increased by one dwelling unit above the number of legally established dwelling units providing the building complies with the following requirements:

   (a)   The alterations meet the requirements of Title 17 of this Code;

   (b)   The building shall not be more than four stories high for ordinary construction (Types III-B or III-C), and not more than two stories high for combustible frame construction (Types IV-A or IV-B). Buildings of mixed ordinary and frame construction shall be governed by the requirements of combustible frame construction;

   (c)   A basement may be used for habitable rooms or a dwelling unit, regardless of the depth of the floor below grade, if the floors and walls are impervious to leakage of underground and surface runoff water and are protected against dampness, and if the required minimum window area is located entirely above the finished elevation of the ground adjoining the building wall in which the windows are located;

   (d)   Area and space requirements of Sections 13-196-470 through and including 13-196-490 shall be met in all rooms, except that at least 80 percent of the floor area of every habitable room shall have a ceiling height of not less than seven feet, six inches. Twenty percent of the floor area of any habitable room may have a ceiling height as low as six feet, eight inches;

   (e)   Natural Light and ventilation shall comply with requirements of Chapter 13-172;

   (f)   Exits shall comply with the exit requirements of Sections 13-200-330 through and including 13-200-360, except that basement dwelling units may have a second exit through a space containing a heating plant;

   An existing building or structure may be increased in height or area up to the limits imposed by Chapter 13-48.

   (g)   If the basement contains a dwelling unit, the entire basement ceiling construction shall be one-half hour rated construction, or the original wood lath and plaster construction;

   (h)   Basement apartments shall be separated from heating plants as required by Section 15-8-190;

   (i)   Any subsequent or additional increase of one unit or more under this provision shall meet the requirements of Section 13-200-240.

(Prior code § 78.1-22; Amend Coun. J. 10-28-87, p. 5549; Amend Coun. J. 6-14-95, p. 2841; Amend Coun. J. 4-29-98, p. 66679, § 2)

 

Notes

Title 17

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