§ 1009.21 EXTERIOR OF STRUCTURES.
   (1)   Compliance. No person shall occupy as owner-occupant or let to another for occupancy any dwelling unit, multiple dwelling, rooming house, rooming unit or portion thereof for the purpose of living, sleeping, cooking or eating therein that does not comply with the provisions of this division.
   (2)   Foundations, walls and roofs. Every foundation, exterior wall, roof and all other exterior surfaces shall be maintained in a workmanlike state of maintenance and repair.
      (a)   The foundation elements shall adequately support the building at all points.
      (b)   Every exterior wall shall be free of holes, breaks, loose or rotting boards or timbers, falling or loose stucco or brick and any other conditions that might admit rain or dampness to the interior portions of the walls or to the exterior spaces of the multiple dwelling.
      (c)   The roof shall be tight and have no defects that admit rain. Roof drainage shall be adequate to prevent rain water from causing dampness in the walls.
   (3)   Stairs, porches and railings.
      (a)   Every outside stair, porch and appurtenance attached thereto shall be constructed so as to be safe for use and capable of supporting a load as determined in the Building Code. These areas shall be kept in sound condition and good repair.
      (b)   Every flight of stairs shall have hand rails that are located as provided by the Building Code.
      (c)   Every porch which is more than 30 inches above grade shall have rails so located and capable of restraining a horizontal pressure as determined by the Building Code.
      (d)   Every rail and balustrade shall be firmly fastened and maintained in good condition.
   (4)   Windows, doors and hatchways. Every window, exterior door and basement hatchway shall be substantially tight and shall be kept in sound condition and repair.
      (a)   Every window shall be fully supplied with window panes that are without open cracks or holes.
      (b)   Every window sash shall be in good condition and fit reasonably tightly within its frame.
      (c)   Every window, other than a fixed window, shall be capable of being easily opened and shall be held in an open or closed position by window hardware.
      (d)   Every exterior door, door hinge and door latch shall be in good condition.
      (e)   When closed, every exterior door shall fit reasonably well within its frame.
      (f)   Every window, door and frame shall be constructed and maintained in relation to the adjacent wall construction as to completely exclude rain and substantially exclude wind from entering the dwelling or multiple dwelling.
      (g)   Every basement hatchway shall be constructed and maintained so as to prevent the entrance of rodents, rain and surface drainage water into the dwelling or multiple dwelling.
      (h)   Every door available as an exit shall be capable of being opened easily and without the use of a key from the inside.