General Requirements

Where Required (R310.1)

  • Basements, habitable attics, and every sleeping room must have at least one operable emergency escape and rescue opening
  • Where basements contain one or more sleeping rooms: each sleeping room requires an opening
  • Openings must lead directly into a public way, or to a yard or court that opens to a public way

Exceptions:

  1. Storm shelters and basements used only for mechanical equipment with total floor area not exceeding 200 square feet (R310.1)
  2. Where dwelling or townhouse is equipped with automatic sprinkler system (Section P2904), sleeping rooms in basements do not require emergency escape and rescue openings if basement has one of the following:
    • One means of egress (Section R311) and one emergency escape and rescue opening
    • Two means of egress (Section R311)

Sizing Requirements

Minimum Net Clear Opening Area (R310.2.1)

  • Standard requirement: 5.7 square feet
  • Grade floor or below grade openings: 5.0 square feet

Minimum Net Clear Opening Height (R310.2.1)

  • 24 inches

Minimum Net Clear Opening Width (R310.2.1)

  • 20 inches

Placement & Positioning 

Sill Height (R310.2.2)

  • Maximum sill height: 44 inches above the floor
  • When sill height is below grade: window well required per Section R310.2.3

Location (R310.1)

  • Must open directly into a public way, or to a yard or court that opens to a public way

Operability

Operation Requirements (R310.1.1)

  • Must be operational from inside the room
  • No keys, tools, or special knowledge required for operation
  • Net clear opening dimensions must be obtained by normal operation from the inside
  • Window opening control devices complying with ASTM F 2090 are permitted

Window Wells

When Required (R310.2.2)

  • Required when window sill height is below grade

Minimum Dimensions (R310.2.3)

  • Minimum horizontal area: 9 square feet
  • Minimum horizontal projection: 36 inches
  • Minimum width: 36 inches
  • Must allow the emergency escape opening to be fully opened

Exception: Ladders or steps may encroach a maximum of 6 inches into required dimensions

Ladder/Step Requirements (R310.2.3.1)

  • Required when: Window well vertical depth exceeds 44 inches
  • Must be permanently affixed
  • Must be usable with window in fully open position
  • Minimum inside width: 12 inches
  • Minimum projection from wall: 3 inches
  • Maximum vertical spacing: 18 inches on center

Drainage (R310.2.3.2)

  • Window wells must be designed for proper drainage by connecting to building's foundation drainage system (Section R405.1) or by approved alternative method

Exception: Drainage not required where foundation is on well-drained soil or sand-gravel mixture soils (Group I Soils per Table R405.1)

Emergency Escape and Rescue Doors

General Requirements (R310.3)

  • Where a door serves as required emergency escape and rescue opening, it must be side-hinged or slider
  • When opening is below adjacent grade: area well required

Minimum Door Opening Size (R310.3.1)

  • Minimum net clear height opening must comply with Section R310.2.1

Area Wells (R310.3.2)

  • Minimum width: 36 inches (914 mm)
  • Must be sized to allow emergency escape and rescue door to be fully opened

Ladder/Step Requirements (R310.3.2.1)

  • Required when: Area well vertical depth exceeds 44 inches
  • Must be permanently affixed
  • Must be usable with door in fully open position
  • Ladders/steps not required to comply with Section R311.7
  • Minimum inside width: 12 inches
  • Minimum projection from wall: 3 inches
  • Maximum vertical spacing: 18 inches on center

Drainage (R310.3.2.1)

  • Area wells must be designed for proper drainage by connecting to building's foundation drainage system (Section R405.1) or by approved alternative method

Exception: Drainage not required where foundation is on well-drained soil or sand-gravel mixture soils (Group I Soils per Table R405.1)

Bar, Grilles, Covers & Screens

Permitted With Conditions (R310.4)

  • May be placed over emergency escape openings, area wells, or window wells
  • Must maintain minimum net clear opening sizes (per R310.2.1 through R310.2.3)
  • Must be releasable or removable from inside
  • No keys, tools, special knowledge, or excessive force required
  • Force required must not exceed that needed for normal operation of the opening

Special Conditions

Under Decks and Porches (R310.2.4)

  • Emergency escape and rescue openings are permitted under decks and porches when:
    • Deck location allows opening to be fully opened
    • Provides a path at least 36 inches in height to a yard or court

Replacement Windows (R310.2.5)

  • Replacement windows are exempt from maximum sill height requirements when:
    1. Window is manufacturer's largest standard size that fits existing frame or rough opening, AND is same operating style as existing or provides equal or greater opening area
    2. Replacement is not part of a change of occupancy

Dwelling Additions (R310.5)

  • New sleeping rooms in additions require emergency escape and rescue openings
  • New basements in additions require emergency escape and rescue openings

Exceptions:

  • Not required in new basement containing sleeping room with its own opening
  • Not required in new basement when existing basement has opening accessible from new basement

Alterations or Repairs of Existing Basements (R310.6)

  • Emergency escape and rescue opening not required for alterations or repairs

Exception: New sleeping rooms created in existing basement must have emergency escape and rescue openings per R310.1

Note: Always verify current code requirements with your local county building inspector, as local amendments may apply.