31 Del. C. ch. 41 § 4113

(a) In general. — The exterior of a structure shall be maintained structurally sound and sanitary so as not to pose a threat to the health and safety of the occupants and so as to protect the occupants from the environment.

(b) Structural members. — All supporting structural members of all structures shall be maintained structurally sound, free of deterioration and capable of safely bearing the dead and live loads imposed upon them.

(c) Exterior surfaces (foundations, walls and roof). — Every foundation, exterior wall, roof and all other exterior surfaces shall be maintained in a workmanlike state of maintenance and repair and shall be kept in such condition so as to exclude rats.

(d) Foundation walls. — All foundation walls shall be maintained so as to carry the safe design and operating dead and live loads, plumb and free from open cracks and breaks, except as necessary to release excessive water pressure on the wall so as not to be detrimental to public safety and welfare.

(e) Exterior walls. — Every exterior wall shall be free of holes, breaks, loose or rotting boards or timbers and any other condition which might admit rain or dampness to the interior portions of the walls or to the occupied spaces of the building. All exterior surface materials, including wood, composition or metal siding, shall be maintained weatherproof so as to prevent deterioration.

(f) Roofs. — The roof shall be structurally sound, tight and not have defects which might admit rain, and roof drainage shall be adequate to prevent rain water from causing dampness in the walls or interior portion of the building.

(g) Decorative features. — All cornices, trim, wall facings and similar decorative features shall be maintained in good repair with proper anchorage and in a safe condition.

(h) Signs, marquees and awnings. — All canopies, marquees, signs, metal awnings, stairways, fire escapes, standpipes, exhaust ducts and similar overhang extensions shall be maintained in good repair, shall be properly anchored so as to be kept in a safe and sound condition and shall be protected from the elements and against decay.

(i) Chimneys. — All chimneys, cooling towers, smokestacks and similar appurtenances shall be maintained structurally safe, sound and in good repair. All exposed surfaces of metal or wood shall be protected from the elements and against decay.

(j) Stairs and porches. — Every stair, porch, balcony and all appurtenances attached thereto shall be so maintained as to be safe to use and capable of supporting the loads to which it may be subjected and shall be maintained in sound condition and repair.

(k) Windows, doors and frames. — Every window, door and frame shall be maintained in such relation to the adjacent wall construction so as to exclude rain as completely as possible and to substantially exclude wind from entering the building.

(l) Weathertight. — Every window and exterior door shall be fitted reasonably in its frame and be weathertight. Weather stripping shall be used as necessary to exclude wind or rain from entering the dwelling or structure and shall be kept in sound condition and good repair.

(m) Glazing. — Every required window sash shall be fully supplied with glazing materials which securely hold in place window glass.

(n) Openable windows. — Every window, other than a fixed window, shall be capable of being opened and shall be held in position by window hardware.

(o) Door hardware. — Every exterior door, door hinge and door latch shall be maintained in good condition. Door locks in dwelling units shall be in good repair and capable of tightly securing the door.

(p) Basement and window hatchways. — Every basement or cellar hatchway or window shall be so maintained as to prevent the entrance of rats, rain and surface drainage into the structure.