CURTAIN WALL JOINT SEALING

Curtain Wall Joint Sealing

The curtain wall joint sealant acts as a fire barrier that slows the progression of fire, heat and smoke between floors of multi-storey buildings.

  1. With the increase in construction of high rise buildings, International building code (IBC) and National building code (NBC) added new fire protection areas.
  •  Perimeter seal or Curtain wall joint seal.
  • Firestop Joint seal

Perimeter seal or Curtain wall joint seal.

Curtain wall joint seal :

  • Building codes requires fire resistance of floor to be extended to outer wall.
  • Glazed outer wall or curtain wall are installed leaving a gap of 100 to 300 mm. 
  • In case of fire in lower floor, the gap become path like chimney for spreading smoke , Heat and Fire 
Curtain wall joint seal
Perimeter seal

Path of fire propagation could be through gap, through outside and also through mullion.

Curtain wall joint seal works as

  • Fire barrier
  • Smoke barrier
  • Acoustics 
  • Preventing loss of air-condition energy
  • A physical barrier for dust etc.
Curtain wall joint seal works as

Six stages of Curtain wall sealing

Six stages of Curtain wall sealing

Standard : ASTM E 2307

Important 

Considerations :

  • Floor construction type
  • Curtain wall construction type
  • Joint width
  • Movement requirement
  • Fire rating
  • Smoke rating
  • Firestop material

Firestop joint seal

Joint between fire resistance rated assemblies shall be protected by an approved fire resistance joint system designated to resist the passage of fire for a time period not less than the required fire resistance rating of the assemblies in which it is installed.

  • Such barriers have L rating for smoke prevention, not in excess of 5 CFM.
  • These may have various expansion/ compression %
  • Joints are tested against UL2079 standard.
  • A joint may be floor- floor, floor – wall , head of wall , wall to wall.
Firestop joint seal
Standard : ASTM E 1966

Standard : ASTM E 1966

Important 

Considerations :

  • Type of joint
  • Nominal width
  • Movement requirement
  • Fire rating
  • Smoke rating
  • Firestop material depth
  • Backer plate