Interior Alterations

More Information

For more information on finishing basements, bathroom remodeling, and other interior alterations, call the Building Department at 847-223-8515 Monday through Friday, 8:a.m. to 5 p.m.

Required Submissions

For interior alterations, you must submit two sets of construction plans showing rooms, equipment and fixture locations, stairs, escape windows, structural items, and relevant notes, etc., properly scaled and labeled.

General Provisions

When finishing a basement or a portion of a basement or space this means that the space is viewed as living space. As such it is required that new finished spaces comply with all aspects of the current building codes including, but not limited to electrical, plumbing, mechanical, and structural systems.

General Items to Consider

  • Ensure the general layout does not restrict access to escape windows, stairways, and means of egress.
  • Provide sufficient access and clearances for maintenance and replacement of plumbing, mechanical, electric, and other system components such as furnaces, water heaters, sump pumps, flues, electric panels, water meters, etc.
  • Provide adequate electric outlets. Spacing is 12 feet maximum as measured along walls.
  • Provide proper lighting at stairs and hallways. A three-way switch is required at the top and bottom of the stairs for stairway lighting control at both levels.
  • All electric wiring must be in metal conduit. Sheathed cable is not permitted.
  • Outlets within six feet of sinks and in bathrooms must be ground-fault type (GFI).
  • Smoke detectors are required in living areas wired in series.
  • All plumbing must conform to the Illinois State Plumbing Code and the Grayslake Plumbing Code including, but not limited to, pipe sizes, vents, joints, cleanouts, etc. Fixtures cannot be used as cleanouts.
  • All under-slab plumbing must be cast iron with leaded joints to above slab piping. PVC schedule 40 pipe is acceptable for above slab applications.
  • Firestopping and fireblocking must be provided at all penetrations and holes through top plates, floors, walls, soffits, and elsewhere per code requirements.
  • Provide proper combustion air for the furnace and hot water heater.
  • Provide proper supply and return air ducts to all spaces as required, all balanced per code regulations. Bathrooms must have exhaust to the outside (one cubic foot per meter for every square foot) or have an operable window of sufficient size.
  • Doors and openings must be minimum of two feet eight inches wide. Bath and storage doors can be two feet six inches wide.
  • A three-foot square area must be maintained in front of the electric panel and at the base of the stairs. Electric panels cannot be located in bathrooms.
  • The underside of stairways must generally be protected with one layer of half-inch drywall.
  • Ceiling height should be minimum seven feet six inches. 50% of the ceiling can be as low as seven feet. Contact the Building Department if your existing basement or space cannot maintain these heights.
  • All structural items should be properly sized for all loads with maximum deflections of L / 360 for floors at 40 price per square foot live load and L / 240 for roofs at 30 price per square foot live load.