Cavity wall
Cavity
wall consists of double walls with a hollow space between them. cavity wall
thickness of outer wall and inner wall may be equal or the inner wall may be
thicker than outer wall. cavity wall hollow is never exceeds 100 mm and it is
uniform through the height. The masonry skins of a cavity wall can be
brickwork, block-work or similar. Different masonry materials can be used on
either side of the cavity. The cavity is initially empty but can be filled with
insulation by various methods. Cavity walls are more time consuming –and
therefore slightly more expensive– to build than walls with the two skins bonded together, but they
provide better sound and heat insulation and most importantly resistance to
rain penetration.
Typical
Flashing Installation at Bearing Support of Cavity Wall
The
following advantage s of cavity wall construction
Damp
Prevention : cavity
wall checks the prevention of dampness from outside to inside of the building
in better way than a solid brick wall of same thickness.
Heat Insulation
: since air is a bad
conductor of heat, a cavity wall decreases the heat transmission considerably
hence it is easier to maintain uniform temperature inside the building.
Sound
Insulation : sound
waves can travel faster in solid media than air, the cavity wall constructions
considerably dampens the external noise and inside the building external
disturbances have little effect.
Economical : The construction cost of
a cavity wall is about 20% less than the construction cost of a solid wall
having same thickness.
Disadvantage
of cavity walls
- Requires a high standard of design and workmanship to produce a soundly construction wall
- Cavity wall require good supervision during construction.
- The need to a vertical dam-proof course to all openings
- Slightly higher cost than a standard one brick thick wall.