Building Envelope

BUILDING ENVELOPE
-Systems, Materials, Methods and Examples

The building envelope as further defined
is the physical separator between the
conditioned and unconditioned
environment of a building including the
resistance to air, water, heat, light, and
noise transfer.
Building enclosures were always
expected to be durable and provide a
degree of environmental separation, but
now they must address issues like energy
efficiency, daylighting, indoor air quality,
fire safety, thermal comfort, and carbon
footprint. There is now a need to explicitly
ensure these performance objectives are
fully satisfied at the design stage.
PARAMETERS
1. Sun Control
Thermal and visual
comfort are dependent
on controlling the light
entering a building
through its facade.
GSW Headquarters Building, Berlin

2. Day Lighting
Daylighting can be
achieved mainly through
passive measures. A
simple light shelf can
bounce light deep into a
space, illuminating the
interior by taking
advantage of the
reflectivity of the ceiling.
GSW Headquarters Building, Berlin

3. Natural Ventilation
Ventilation strategies can
also give a strong
character to the elements
of a facade.
They can be simple, small,
repetitive louvers that
allow for localized air
circulation, or very
involved mechanical
systems that direct fresh
air throughout the
building.
Light Shelf in an office
4. Connection to Outdoors
Connection to the outdoors is another
sustainability feature that is psychological in
nature, like daylighting.
5. Thermal Insulation
The invisible insulation in walls has a huge
potential to impact the thermal
performance of a building. A particular
insulations makeup and placement within
the layering of the building skin can have
large consequences that are observable in
the thermal performance and aesthetics of
the building skin
6. Moisture Control
The rainscreen and moisture barrier work
together to prevent unwanted rain and
condensation from entering the building
7. Structural Efficiency
High-rise construction is primarily
concerned with carrying lateral loads, so
the diagonal lateral bracing of the building
often called the Gherkin is expressed as
part of the skin, helping to define the
character of the building.
8. Material Choices
Materials can give a very distinctive
character to a building Although they are
often overlooked by students and
professionals early in the design process,
materials are seminal because their texture
and appearance define the experience of
the building. Materials also play a primary
technological role and have a tremendous
effect on the comfort of the building.
9. Possibility for Energy Generation
There is also the possibility for a buildings
skin to become an energy source.
Photovoltaics can be integrated into
facades.
Any serious inquiry into this context must address the following questions,
vitally important to the theory and analysis and to the planning and design:
1. Function: What is the practical purpose of the building /

the building skin?
2. Construction: What are the elements/components of
the building/the building skin and how are these elements
assembled into a whole?
3. Form: What does the building/the building skin look like?
COMFORT AS
PARAMETER IN
BUILDING SKIN
DESIGN
Indoor air temperature
The comfort zone for indoor air temperature
ranges from 2025 C maximum. In summer,
temperatures of up to 27 C are still
considered tolerable. When internal wall
surface temperatures and the relative indoor
humidity are properly adjusted, indoor air
temperatures as low as 18 C are still
perceived as comfortable.
Common Standards Used: ASHRAE Standard-

Ventilation for Acceptable Indoor Air Quality
Average surface temperatures
Whenever possible, these temperatures
should differ by no more than 23 K from the
indoor air temperature; the differential
between various surface temperatures in
surrounding areas should not exceed 34 K.
Air change and Air Movement
While a minimal air change rate of 0.3/h is
sufficient in unoccupied rooms, this value rises
to 1.1/h during work hours. This corresponds to
a fresh air intake of 4060 m3/h per person.7
Generally a value of 200 cm2/m2 of floor area
suffices for intake and ventilation openings for
natural ventilation. At the same time it is
important to avoid draughts by
ensuring that air velocity does not exceed
0.15 m/s.
Relative indoor humidity
Depending on room temperature, the
comfort zone for relative indoor humidity
ranges between 30 and 70 %. Grand- jean 10
establishes a more limited range of
comfortable
relative indoor humidity, between 40 and 60
%.
Luminance
The standard values for luminance at the work
place are dependent on the activity, the
room layout and the proximity of the
workstation to windows. Typical values lie in
the region of 300 lx for workstations near
windows, 500 lx for standard cubicle offices
and 700 lx for open-plan offices with a high
degree of surface reflection or 1000 lx for
open-plan offices with medium surface
reflection.
Standards Used: DOE Guidelines for Energy

Conservation Design of Buildings
Lighting intensity
The quality of lighting in a room is not only
influenced by luminance but also by glare. It is
important to select and position glare
protection elements in a manner that
provides evenly distributed daylight without
glare, while avoiding unnecessary cooling
loads in the interior space.
COMFORT AND
ENERGY-RELATED
PARAMETERS OF THE
BUILDING SKIN
U-value
The thermal transmittance (formerly U-value) indicates the amount of
heat which passes through external wall structures in W/m2 K.
G -value
The total solar energy transmission (g-value) indicates the percentage
of solar radiation (wavelength 3202500 nm) transmitted through
transparent or translucent external walls.
Diminution factor
The diminution factor indicates the proportion of incident radiation
passing through a solar-shading system.
Daylight transmission factor

The daylight transmission factor is a measure of the percentage of
daylight present outside the building and perceivable by humans
(wavelength 320780 nm) that passes through the glazing.
ANTI-GLARE SYSTEMS
Curtains
Horizontal blinds
Vertical blinds
Venetian blinds
Screens
Translucent glazing
Electrochromic glazing
Electrochromic glass ("smart" glass), which changes

from light to dark (clear to opaque) and back again, at
the push of a button.
Electrochromic glass ("smart" glass), which changes

from light to dark (clear to opaque) and back again, at
the push of a button.
DAYLIGHT USE
Glazing with selective coatings

DAYLIGHT USE
Reflectors that deflect daylight into the depth of a

room
DAYLIGHT USE
Micro-grid systems with high reflective coatings

Prism systems
Movable Prism Systems

DAYLIGHT USE
Light-diffusing glazing
Light Diffusing Insulating Glass

DAYLIGHT USE
Glass louvre systems

DAYLIGHT USE
Holographic defractive system (HDS)
Holographic Panels
ILLUSTRATIVE EXAMPLES
OF BUILDING SKINS/
ENVELOPE
Allianz Arena
Herzog & de Meuron, Basel
EFTE sheeting
(Ethylene/tetrafluoroethylene copolymer)
Fixing method: The cushions, each made up of at
least two layers, were pre- tensioned and
stabilized by means of excess pressure in the
enclosed air volume.
Installation
Allianz Arena
Allianz Arena
Selfridges Department Store in
Birmingham
Architects: Future Systems, London
Domed aluminium discs

Polished and Naturally Anodized
Fixing method: First the mounting plates were fixed to the outer
Installation layer (which was strengthened in the area in which the discs are
attached). Then the discs centred on these plates and fixed.
Selfridges Department Store in Birmingham
Architects: Future Systems, London
Prada Flagship Store in Tokyo Fixing method: Each pane is fixed by
Architects: Herzog & de Meuron, Basel means of two clamps on opposite
sides. The panes stay in position
even under conditions of severe
earth tremors,
the frame itself slides at the edge
connection with the panes.
RHOMBOID GLASS ELEMENTS

flat, convex and concave
Prada Flagship Store in Tokyo
Architects: Herzog & de Meuron, Basel
Faade Section
Prada Flagship Store in Tokyo
Architects: Herzog & de Meuron, Basel
Bibliography
Bixby, D. (2009). Building Skin as a Connector. Proceedings of the 7th International Space Syntax Symposium .
McIntosh, M. (n.d.). Sustainable Building Skin Design. University of Texas and Austin.
Schittich, C. (2006). In Detail: Building Skins. Germany.

Building Envelope

Uploaded by

Copyright:

Available Formats

Building Envelope

Uploaded by

Document Information

Original Description:

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Building Envelope

Uploaded by

Copyright:

Available Formats

BUILDING ENVELOPE

-Systems, Materials, Methods and Examples

GSW Headquarters Building, Berlin

GSW Headquarters Building, Berlin

1. Function: What is the practical purpose of the building /

Common Standards Used: ASHRAE Standard-

Standards Used: DOE Guidelines for Energy

Daylight transmission factor

Electrochromic glass ("smart" glass), which changes

Electrochromic glass ("smart" glass), which changes

Glazing with selective coatings

Reflectors that deflect daylight into the depth of a

Micro-grid systems with high reflective coatings

Movable Prism Systems

Light Diffusing Insulating Glass

Glass louvre systems

Holographic defractive system (HDS)

Domed aluminium discs

RHOMBOID GLASS ELEMENTS

You might also like