14 DCMR § 14-502
LIGHTING IN HABITABLE ROOMS
Operative Text
502.1 Each habitable room shall have a glass area transmitting natural light equivalent to that which would be transmitted by a clear glass area at least equal to one tenth (1/10) of the floor area served, consisting of one or more of the following: (a) Windows; (b) Glazed doors; (c) Glazed doors with either or both side lights or transoms; or (d) Other glass construction facing directly to the outside. 502.2 Rooms opening on enclosed porches and meeting the lighting requirements of Article 501-01-e of the 1941 Building Code, as amended (Title 12, DCMR) and rooms lighted through sunporches and meeting the lighting requirements of § 3-515 of the 1961 Building Code, as amended, shall be deemed to have adequate natural light. 502.3 The sash area of openable windows, side lights, or transoms, the horizontal projection of the glass area of skylights, and in all other instances the gross glass area, shall be used in computing the required glass area. 502.4 Any portion of any glass area facing directly on any wall, portion of a structure, or other light obstruction less than three feet (3 ft.) from that glass area, shall not be included as contributing to the required natural light. 502.5 At least fifty percent (50%) of the required glass area shall be a window, glazed door, side light, or transom, each glazed with clear glass. 502.6 Obscure glass, glass blocks, or other approved translucent material may be used to transmit up to fifty percent (50%) of the required natural light.
Under D.C. Mun. Regs. tit. 14 et seq. § 14-502, every habitable room in the District of Columbia must receive natural light through glass openings totaling at least one-tenth of the room's floor area. That glass can come from windows, glazed doors, skylights, or similar transparent construction facing the outside, though glass blocked by a wall or structure within three feet does not count toward the requirement. At least half of the required glass area must be clear glass, while obscure glass or glass blocks may account for no more than the other half.
Plain English — not legal advice.
Property owners and managers operating in the District of Columbia should ensure that every habitable room meets the natural-light standard set out in D.C. Mun. Regs. tit. 14 et seq. § 14-502 by verifying that qualifying glass area equals at least one-tenth of each room's floor area. Compliant operators typically confirm that at least 50% of that glass area consists of clear windows, glazed doors, side lights, or transoms, and that no qualifying glass is obstructed by a wall or structure within three feet. Rooms served by enclosed porches or sunporches may qualify under the referenced 1941 or 1961 Building Code provisions, so operators often document how those spaces meet the alternative standards described in § 14-502.2.
General guidance for property managers — not legal advice for your specific situation. Consult an attorney for advice on your case.
Tenants living in the District of Columbia have a right to habitable rooms that meet the natural-light standards established by D.C. Mun. Regs. tit. 14 et seq. § 14-502, which requires sufficient clear glass area relative to each room's floor space. If a room appears to lack adequate natural light — for example, because windows are too small or are blocked by a nearby structure — that condition may constitute a housing code violation that can be reported to the District's housing inspection authorities. Tenants can also consult a local tenant-rights organization to understand how a violation of § 14-502 might be raised in a housing complaint or used as a defense in related proceedings.
General guidance for tenants — not legal advice for your specific situation. Consult a tenant-rights organization or attorney for advice on your case.
Generated October 13, 2026 — auto-generated, not yet human-reviewed. See /transparency for methodology.
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