Transcript Lecture 22

Lecture 22- Exterior Cladding
Systems a.k.a skins
ARCH 330
Materials & Methods
Fall 2008
Cladding/ Curtain Wall
• Constructed in Place
• Prefabricated
Cladding
A.K.A
Skin
Curtain Wall – glass + metal systems
Cladding
• Non-load bearing exterior wall enclosure.
• Most visible, most subject to attack by
natural forces.
• Separates indoor environment from
outdoors in such a way that the indoor
environment can be maintained at a level
suitable for the building's intended use.
Primary Functions of Cladding
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Keep Water Out
Prevent Air Leakage
Control Light (heat, glare, ultraviolet)
Control Radiation of Heat
Control Conduction of Heat
Control Water Vapor
Control Sound
Secondary Functions of Cladding
• Resist Wind Forces:
• Adjust to Movement:
Thermal expansion and contraction,
Moisture expansion and contraction,
Structural deflections.
• Resist Fire
• Weather Gracefully
Forces that Move Water
• Gravity
• Momentum
• Surface Tension
• Capillary Action
• Wind/ Air Currents
Rainscreen Principle
• Let wind pressure differences between the
outside and inside neutralize themselves
PEC
Pressure Equalization Chamber
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Pressure equalized wall design
Airtight barrier at the internal side
Rainscreen - loose fitting jointed layer
Current of air can pass back and forth
through the unsealed joints.
Sealant Joints in Cladding
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Fill/seal the joints
Prevent flow of air and/or water
Permit assembly tolerance
Permit movement
Design Process - Prefabricated
(a) Curtain wall manufacturer selected and
made a part of the building design team
from the first stages of the project.
(b) The architect prepares a rough design and
performance specification and submit these
to several manufacturers for proposals.
STICK
1. Anchor
2. Mullion
3. Horz rail
4. Spandrel panel
5. Horz rail
6. Glass
Constructed in Place
Stiffening Method
• Steel Sub Frame
• Back-up Wall of Masonry
• Back-up Wall of Light Gauge
Studs
Prefabricated
Method of Assembly
• Stick
• Unit
• Unit + Mullion
• Panel
• Column Cover + Sprandrel
Masonry
• Constructed in place
• Prefabricated
Metal + Glass
• Prefabricated
Structural Glass
Gehry - Guggenheim
Nicholas
Grimshaw
and Partners
Ludwig Erhard Haus
Financial Centre