facade cladding .research_team_erz_2013.22.10_arch.2430

Report
FACADE CLADDING
 Metal Panel, Rigid Insulation
 Stone veneer Panels
TEAM: ERZ
BUILDING TECHNOLOGY 4
MONIRUZ ZAMAN, ELVIS CHATTERPAUL, RACHIDA
AIR BARRIERS & SEALANTS
•
Insulated metal panels qualify as Continuous
Air Barriers. By keeping the internal and
external environments separate, CABs
enhance energy efficiency and are required
by newer energy efficiency building codes
and standards. The ability of the panels to
seal to each other, as well as to the structure
provides an excellent air barrier. This is why
Insulated metal panels work so well at
stopping the vapor drive between the interior
and exterior of structures. By sealing the
panels so well to each other and to the
structure, moisture laden air is unable to pass
from the warm side of the wall to the cooler
side, greatly reducing the chance of
condensation on the interior of the building
or within the walls.
AIR BARRIERS & SEALANTS
• Stone cladding is a thin layer of real or simulated stone applied to a structure
made of material other than stone. It is applied to concrete and steel buildings
to comply with their original architectural design.
• Stone veneer panels do not provide a sufficient air barrier to a structure. The
air barrier is derived from the actual wall that the stone is being placed on. It is
essentially for atheistic use only.
ATTACHMENT SYSTEMS
• Insulated metal
panels often
require fewer
structural supports
than single skin
panels because of
their enhanced
spanning and load
bearing capabilities.
This provides an
efficient and
economical building
envelope.
ATTACHMENT SYSTEMS
Insulated Metal
Panel
BASE ANGLE
WALL PANEL CLIP
NON-SKINNING BUTYL SEALANT
CONCRETE
ANGLE TRIM
FASTENER
SILL TRIM
URETHANE SEALANT
ATTACHMENT SYSTEMS
& FIRE SAFETY
• Typically stone cladding is affixed
to the wall of a structure using a
mortar mix. Using natural stone can
be heavier than simulated stone,
which often needs mechanical
fixing to be adhered to a structure.
Anchors must be used to attach and
support the stone panels to the
building's primary or secondary
framing system. Mechanical fixing
could be using shelf angles or a
stone clip. Lightweight structures
would use plywood bracing as an
alternative to fiber cement sheets.
ATTACHMENT SYSTEMS
& FIRE SAFETY
• Stone wall systems are not
considered to provide any
improvement in fire safety for
the building exterior wall. In
high-rise buildings stone wall
systems can pose a serious
safety hazard when a fire
occurs that breeches the
exterior envelope. When stone
is exposed to intense heat from
fire it can crack and the
cracked portions of stone can
fall from the building, putting
lives in danger from falling
stone.
THERMAL INSULATIONS & R’
VALUES
•
•
Insulated metal panels provide continuous insulation.
This means that insulation runs continuously across all
structural members without thermal bridges. This is
accomplished by utilizing a concealed clip and a double
tongue-and-groove interlock, effectively creating a
thermal break between the exterior panel skin and the
interior panel skin. Continuous insulation is important
because thermal bridges and discontinuities introduced
by compressing non-rigid insulations cause the in-place
R-value of the assembly to be less than the tested Rvalue of the insulation used.
With the insulating capabilities of insulated metal
panels, less insulation space is needed to comply with
building energy efficiency codes compared to fiberglass
systems. Buildings using non-rigid insulation, such as
fiberglass, can require up to four times the amount of
insulation space compared to insulated metal panels.
Insulated metal panels do not experience significant
thermal drift due to the metal exterior and interior skins
of the panels combined with the closed cell structure.
THERMAL INSULATIONS & R’
VALUES
• Thin stone wall
systems derive their
thermal
performance
characteristics
primarily from the
amount of insulation
placed in the wall
cavity or within the
backup wall. The
stone and
supporting elements
of the wall provide
little to no insulating
value.
METAL PANEL CONNECTIONS
• Metal panels are assembled as a
unit at the shop and brought to the
site to be attached to the building.
By the use of various clipping
systems the panels are attached to
studs or the exterior wall system.
METAL PANEL ASSEMBLY
• Metal panels are
assembled with each other
and are best placed when
used by the specified joint
type. They are attached to
the exterior wall or studs
with screws and clips.
METAL PANEL ASSEMBLY
• Metal panels can be
attached to steel
structural elements
and concrete
structural elements
such as beams.
STONE VENEER PANELS
• Stone veneer panels are attached to
a building by using a clipping system
on the stone element and the
building’s element which will hold
the panels. The panels are uniquely
marked and each panel has to be
placed at the correct location of the
building.
STONE VENEER PANELS
• Stone veneer panels are assembled in various ways depending on the
manufacturer, but usually it is assembled like the picture above.
Several layers are attached to each other to form the finished form of
a stone panel that will be clipped to a structure.
STONE VENEER PANELS
3-d figure of the general assembly of stone veneer panels with
other elements of building.
CASE STUDY BUILDINGS
Glazer children’s museum
Architect: Gould Evans
Location: 288 Aviation Avenue South
Burlington, VT USA.
• The Glazer Children's Museum had only a 16-month
construction and move-in timeframe and it required exterior
cladding that could be installed quickly. The design team also
wanted a striking building to serve a demonstration tool, that
taught children about sustainability and protecting the
environment.
CASE STUDY BUILDINGS
• The Glazer Children's Museum used the panel system in the facade
because of how quickly it can be assembled and installed. The subtle
grayish panels allow the more colorful parts of the building stand out and
communicate with the children.
CASE STUDY BUILDINGS
Chesapeake Energy building
Oklahoma city, Oklahoma
Completion: march 2012
Construction Type: Facade Renovation
• After a severe hailstorm, the
exterior panel system was
damaged a lot. Originally, it was
planned to remove all damaged
panels and replace them with
new panels. After realizing that
the panels and glass were very
integrated with each other,
therefore, only removing the
panels was not possible. It
would cost too much and take
too much time to replace both
the panels and the glass.
CASE STUDY BUILDINGS
• So a “over-cladding” system
was used. New panels would go
on top of old panels and the old
panels would serve as air and
moisture barriers. If it were to be
damaged again, they can take
only the damaged panels from
the newly installed ones which
aren’t very much connected with
the glass.
CASE STUDY BUILDINGS
NYCCT VORHEES BUILDING
Brooklyn, New York
Construction Type: Renovation
• The Voorhees building was
completely renovated for a
better look and functionality.
The ground level exterior
around the building is a stone
veneer cladding. It gives a clean
smooth look and a sense of solid
feeling compared to rest of
building’s façade. which is a
curtain wall system. This system
was most likely used as part of
the façade due to the fact that
stone us very good against
moisture, it is cost efficient, and
easy to install.
CASE STUDY BUILDINGS
• While under construction,
the stone is covered with
plastic while the jointing
mixture is settling to
control moisture from
getting onto the mixture.
Rainscreen system
• How it works?
The purpose of a rainscreen system is to keep
water out of a building :It works like a water
barrier.
This system is designed by keeping the cladding
separated from the building through the uses of
furring strips or a specialized rainscreen
products.
The efficacy of the system depend on the spacing
between the cladding and the exterior wall as it
can change the way the water penetrate through
the structural wall assembly.
Rain Screen Wall. A “rain screen” approach resists rain penetration in three
ways:
1) the exterior cladding layer sheds most water at its outer surface;
2) it anticipates that some water will penetrate behind the outer surface, and intercepts
it with a dedicated air space/capillary break; and
3) this space is vented to the outside to not only assist drainage but to encourage drying as
well. The air space or capillary break allows more free drainage than the “concealed
barrier, "diverting water downward by gravity.
The air space /capillary break is typically at least 3/8" in width, and can be kept
open by spacer materials (furring, drainage mats, profiled boards, and the like)
which have been shown to provide superior “drainage efficiency.”9 Finally,
venting the air space to the outside not only assists drainage but encourages
additional drying as well. This is important, since the “drying rate” can be more
significant than “drainage” for long-term performance and durability of exterior
building walls.
FORMS OF RAINSCREENS
1- Ventilated rain screen system
Featured a continuous air space open
at top and bottom to encourage
airflow and convective drying when
water gets between the cladding and
the exterior wall of the building due
to wind –driving rain, bulk water
shedding , or capillary actions
through porous cladding.
The cavity must be protected with
overhangs and screens so that bulk
water and insects will not get in.
A continuous moisture barrier
should be used in addition to the
rain screen system and a
Water resistant rigid insulation
PRESSURE EQUALIZED
RAINSCREEN SYSTEM
The previous system
assumes that water will
inevitably get behind the
cladding . In contrast, a
pressure equalized
rainscreen system are
designed to prevent
moisture from entering in
the first place. Even though
this system allows drainage
it cannot be open at the top
as this will prevent
pressure equalization.
The pressure equalized system is
compartmentalized into discrete chambers,
taller than they are wide. These ventilation
cavities respond to constantly changing
wind pressure.
When the wind enter from the bottom and
can’t find a way out, the air pressure
inside the cavity pushes the wind back
stopping water from entering
Natural stone panels
and Metal panels
Natural stone, metal panels, and
architectural precast concrete wall
cladding systems are similar in that
they are large format panels that are
attached at discrete points to their
structural backup . The panels rarely
leak -- 40 mm of granite, 1.2 mm of
aluminum and 4" of concrete are all
essentially perfect barriers. However,
the large numbers of joints between
panels do often leak, since sealant
cannot be perfectly applied and will not
last indefinitely. Hence, these systems
should be designed as drained systems.
It is relatively easy and inexpensive to
apply a drainage plane and a cavity
behind such systems.
METAL PANEL & STONE VENEER
RAINSCREEN SYSTEMS
The popularity of
ventilated rainscreen
systems have found there
favor for Metal Panels as
well as stone veneer. The
key benefit is the
elimination of the joint
sealer, which requires
maintenance, collects dirt
and can stain or discolor
the metal panels.
Additionally the natural
ventilation adds to the
longevity and thermal
performance of the façade.
GENERAL RAINSCREEN BENEFITS
• Eliminates exposed sealants at critical transitions
(less maintenance).
• Dramatically reduces air infiltration through pressure
equalization as well as more effective air barrier
placement.
• Eliminate mold/mildew from interior space.
• Back ventilation allows for quick moisture evaporation,
thereby extending the life of the cladding, insulation,
sub-framing.
• Air space behind the claddings, dissipates radiant heat
through the chimney effect.

similar documents