Case 4
- Introduction
- Causes of Defects
- Good Practices
- Standards
- Maintenance and Diagnostics
- Remedial
- Similar Cases
- References
Remedial
The best way to prevent direct rain entry is to reseal all openings, expansion joints, cracks, failed joints, cracks, failed joints between window frames and cladding (except vents and drains or a rain screen system).
Gravity is the most frequent cause of water drainage inside the building. To deal with such a problem, openings can be provided at horizontal discontinuity below openings through which leakage can be fed outwards. If the window sill is cut short and unsealed at the end or sloped in the wrong direction, water will flow directly into the room.
Flashing and sill devices should always be positively sloped more than the 15° to the outside of the building.
The pressure differential can be prevented by adopting the pressure equalizer principle, no longer relying on the closure of all holes but rather on the equalizer pressure in the cavity between the external and internal skin of the curtain wall. The design consists essentially of an outer wall (the rain screen) and inner partition (the air barrier) which is separated by a cavity vented to the exterior through weep holes to the atmosphere