A Sustainable Design Practice

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Sun Controls A Sustainable Design Practice

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Sun Controls: A Sustainable Design Practice

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Purpose and Learning Objectives

Purpose:

Currently, buildings are the single biggest contributor to GHG emissions, accounting for roughly half of all energy

consumption in the U.S. and globally. It is crucial to reduce this level of consumption by including high-performance

envelope strategies such as shading systems in all new building designs. In this course, we look at shading systems,

examine shading and design strategies, and learn tips for successful selection and design.

Learning Objectives:

At the end of this program, participants will be able to:

• identify economic, environmental, and human performance factors that support sustainable shading and daylighting

design

• recall shading dynamics and the role of modeling

• explore effective strategies for optimized thermal performance and interior illumination

• consider sun control design options, construction methods, and crucial engineering considerations, and

• establish a decision process for design and selection of sustainable shading and daylighting systems.






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Contents

The Problem

Benefits of Sun Shading

Shading Strategies

Designing Sun Shading

Design Strategies

Light Shelves

Summary

Click on title to view






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The Problem






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The Problem

According to Architecture 2030, “The urban built environment

is responsible for most of the world’s fossil fuel consumption

and greenhouse gas emissions.

Over the next twenty years, an area equal to a staggering 3.5

times the entire built environment of the U.S. will be

redesigned, reshaped, and rebuilt globally. If all these buildings

are designed and constructed using traditional inefficient

approaches, and are powered by electricity produced by

burning fossil fuels, there is no way to avoid irreparably

damaging the planet’s climate.”

Architecture 2030 is a non-profit think tank whose mission is to

transform “climate change problems into solutions through the

design of the built environment.” They have put forth a

challenge to architects worldwide to transform the building

sector from a major contributor of greenhouse gases to a

significant part of the solution.






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The Problem

In the United States, buildings consume nearly half of

all energy produced. Industry and transportation each

use around half of the amount consumed by

buildings.

In the U.S., seventy-five percent (74.9%) of all

electricity produced is used just for building

operations. Globally, these percentages are even

higher.

If we look at greenhouse gas (GHG) emissions,

buildings are once again the greatest single

contributor to CO2 emissions in the U.S. They are

responsible for almost half (44.6%) and more than

double that of industry (21.1%).

Industry 24.4%

(23.2 QBtu)

Buildings 47.6%

(45.2 QBtu)

Transportation 28.1%

(26.7 QBtu)

U.S. Energy Consumption by SectorSource: © 2013 2030, Inc. / Architecture 2030. All Rights Reserved.

Data Source: U.S. Energy Information Administration (2012).






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The Problem

If we dig down deeper into the building sector, we

see that building operations (HVAC, lighting, and

any process using energy in the building)

consume 41.7%, and building construction and

materials account for roughly 6%.

Clearly, buildings are big targets in terms of

energy use in the U.S. and potentially part of the

solution to try to reduce our energy consumption.

Industry

24.4%

Buildings Operations

41.7%

U.S. Energy Consumption by SectorSource: © 2013 2030, Inc. / Architecture 2030. All Rights Reserved.

Data Source: U.S. Energy Information Administration (2012).

Transportation – Light Duty

(auto, SUV, pickup, minivan)

16.3%

Building Construction

and Materials

5.9%

Transportation – Other

(rail, air, bus, truck, ship)

11.8%






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The 2030 Challenge

The main idea of Architecture 2030 and the 2030

Challenge states:

Starting today, all new buildings, developments, and major

renovations shall be designed to meet a fossil fuel, GHG-

emitting, energy consumption performance standard of

70% below the regional (or country) average/median for

that building type.

The fossil fuel reduction standard for all new buildings and

major renovations shall be increased to:

• 80% in 2020

• 90% in 2025, and

• carbon-neutral in 2030 (using no fossil fuel, GHG-

emitting energy to operate).

This challenge is directed at architects to design high-

performance buildings.






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The 2030 Challenge

There are numerous strategies and resources

available from Architecture 2030 to help

designers meet the 2030 challenge targets.

By utilizing some of the innovative design

strategies available, implementing new

technologies and systems for on-site

renewable energy systems, and limiting the

need for off-site renewable energy to a

maximum of 20%, buildings can be designed

and constructed to meet the challenge.

In doing so, this can change the built

environment from a major contributor to the

problem into a central part of the solution.

DESIGN

STRATEGIESThe largest energy

reductions can be

achieved through

design.

OFF-SITE

RENEWABLE

ENERGY20% maximum.

Meeting the 2030 ChallengeSource ©2010 2030, Inc. / Architecture 2030. All Rights Reserved.

TECHNOLOGIES

AND SYSTEMSIncluding on-site renewable

energy systems.






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Solving the Problem

Design strategies implemented to reduce the energy load of buildings

directly impact the ever-increasing demand for more fossil fuel power

plants that continue the cycle of CO2 emissions and damage to the

environment.

One of the most essential to energy savings is the creation of a high-

performance building envelope. In this course we will be looking at sun

control systems as one strategy to reduce cooling costs and energy use.

Trying to control the amount of solar heat gain through glazing, be it

vertical or skylight glazing, while reducing the dependence on artificial

lighting by natural lighting is our focus.






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The use of sun shading will impact a

number of areas of building design:

• sustainable building design

• effects of direct solar heat gain

• building HVAC and lighting design

• occupant visual and thermal

comfort

• aesthetics

• capital costs

• life cycle costs

The relative importance of each impact

will vary from client to client and project

to project.






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Direct and indirect benefits for building owners

include:

• increased occupant satisfaction,

productivity, and/or retail sales

• lower HVAC costs (initial and life cycle)

• lower lighting costs (initial and life cycle),

and

• fixed costs today versus an uncertain life

cycle cost tomorrow (energy).

Potential occupant benefits (government, hospital,

and education) include:

• positive environmental and energy

impact

• reduced patient recovery time, and

• improved student and work performance

of 5 to 14% in daylit conditions.






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LEED® v4 Credits

The most familiar sustainable building certification program is the U.S.

Green Building Council’s Leadership in Energy and Environmental Design®

program, better known as LEED.

There are a number of different ways sun control systems can contribute to

accumulating LEED credits across several categories, such as:

• Energy and Atmosphere – Optimize Energy Performance,

possible 20 points

• Indoor Environmental Quality – Daylight and Quality Views,

possible 4 points (combined), and

• Materials and Resources – Building Product Disclosure and

Optimization – Material Ingredients, possible 2 points.

Clearly, the greatest potential for credits can be realized in the Energy and

Atmosphere category.

LEED® is the preeminent program for the

design, construction, maintenance and

operations of high-performance green buildings.






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LEED v4 Credits

Products can contribute toward earning two points in

LEED v4 Building Product Disclosure and Optimization –

Material Ingredients, Option 1: Material Ingredient

Reporting and Option 2: Material Ingredient Optimization.

One potential way to get points for sun shading products

in this category is to use Cradle to Cradle Certified™

products, which are rated in several quality categories

including material health, material reutilization, renewable

energy and carbon management, water stewardship, and

social fairness.

Other options for contributing to points in the Building

Product Disclosure and Optimization category include

Health Product Declaration®, GreenScreen®,

Environmental Product Declaration® or the Sourcing of

Raw Materials, Option 2: Leadership extraction practices:

Recycled content.

Cradle to Cradle Certified™ products quality categories






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LEED v4 Credits

Of the 110 potential LEED points in a LEED

project, 35 of them can be gained in the

Energy and Atmosphere category, so it is

reasonable to make this category the main

target.

In particular, we want to focus on optimizing

the energy performance of the building. Using

energy modeling compared to the ASHRAE

baseline, designers can predict energy

improvements based on design alternatives.

The greatest optimization of various sun

control systems can be offered when

combined with interior light shelves. Sun

controls/light shelves are specifically cited and

contribute toward an optimized envelope.






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Shading Strategies






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Sun Control System Design

Shading and light control designs have to respond to site and

climate conditions. Different conditions will require different

systems to manage the impact of the sun on the building.

Shading devices can significantly reduce heat gains from solar

radiation while maintaining opportunities for daylighting, views,

and natural ventilation.

A properly designed shading device will:

• cut off solar heat gain in summer and

• harvest solar heat gain in winter.

Through building modeling, sun control system design can be

optimized for the greatest benefit visually and functionally.

SUMMER

(shaded)

WINTER

(not shaded)






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Shading Strategies

Basically, there are two types of

shading systems: internal and

external.

Internal systems are often adjustable

and movable. This can offer flexibility

and reduced costs. Solar gain

through a window can be reduced in

the order of 20%. This can

considerably lower heat gain during

the cooling season.

External systems are generally fixed

to the building. Solar gain can be

reduced by up to 80%. This can

drastically lower heat gain during the

cooling season.






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Shading Strategies

Windows are typically the focus of

shading devices, although roofs and

walls can also benefit from a reduction

of direct solar heat gain.

In some situations, the entire

structure, as well as adjacent

pedestrian spaces such as courtyards,

walkways, and other hardscape areas,

can benefit from shading devices.

The use of large-scale shading

devices can contribute to reducing the

urban heat island effect.






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Solar Protection of Glazing

Everyone wants bigger windows, more glass, or

the corner office. Dramatic views and sightlines

bring the outdoors in; we all want some kind of

connection to the outside world.

So what’s the problem here?

Despite the necessity and desire for glazing, it

remains the least energy efficient portion of the

envelope. In all climates, the more glass we add,

the more we are increasing the demand on the

building’s HVAC system. This increases our

energy consumption and subsequently further

contributes to our GHG emissions.

How can we prevent this from happening?






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Solar Protection of Glazing

With glass you have two opposing factors: the solar heat gain coefficient

(SHGC) and the visible transmittance (VT) factor.

If you specify glazing, you’re familiar with SHGC. This is the fraction of

incident solar radiation that enters through a window. In a cooling climate,

we want the lowest SHGC value possible. Values are between 0 and 1.

Visible transmittance (VT) indicates the fraction of visible light transmitted

through the window. Different types of tint, the number of glass panes, and

the size of the frame will affect this number. Ideally, if you’re trying to create

a daylit environment, a higher visible light transmittance is required. Values

are between 0 and 1.

By choosing engineered glazing systems, we can improve the performance

of our glazing, reducing the load on the HVAC system.






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Review Question

How do exterior shading devices contribute to sustainable buildings?






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Answer

Exterior shading devices make buildings more sustainable by:

• Reducing direct solar heat gain of roofs and walls

• Reducing solar heat gain through glazing while maintaining views and daylighting

• Reducing cooling loads and energy consumption

• Reducing heat island effect

• Maximizing daylighting and reducing use of artificial lighting






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Designing Sun Shading






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Basic Concepts

To properly configure a sun shading system, we

need to use accurately modeled sun studies. Sun

studies identify the following:

Solar altitude is the angle up from the horizon.

Zero degrees altitude means exactly on the

horizon, and 90 degrees is directly overhead.

Solar azimuth is the angle along the horizon, with

zero degrees corresponding to true north, and

increasing in a clockwise direction. So 90o is east,

180o is south, and 270o is west.

Using these two angles, one can describe the

apparent position of the sun at a given time.






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Basic Concepts

Once we’ve collected the necessary

data, the next step is to determine

what conditions we are designing

for.

For Northern Hemisphere projects,

we know the sun is at its highest on

June 21 and at its lowest on

December 21.

Depending on the orientation of the

glazing, we can determine the best

configuration based on how many

days we want shading (to reduce

cooling loads) and how many days

we want sun (to reduce heating

loads).






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Basic Concepts

Typically, when we think about sun

shading, our first thought is in regard to

southern exposures. In these situations

horizontally oriented projections are most

often used.

But what about east and west exposures?

For these configurations, horizontal

systems don’t work as well due to lower

sun angles in the mornings and evenings.

In these situations, vertically oriented

systems excel.

Glazing

Orientation

Glazing

Orientation






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Modeling Performance

In the past, a lot of calculations and manually constructed models were used to perform sun studies. With the latest

software, extremely accurate and complex designs can be studied, altered, and redesigned easily, usually long before

final decisions need to be made.

More and more CAD and 3D applications are providing the ability to perform these studies with the basic software. It is

no longer necessary to use highly specialized, difficult to learn, proprietary applications to perform these studies, allowing

designers greater freedom to experiment and find solutions to problems before they exist.

Also, with these advanced shading modeling programs, you can start to look at what is happening to the light that enters

the building. While deciding what system to implement on the exterior, the effect each configuration has on the interior

environment becomes easy to visualize.

New design ideas and innovations can be applied virtually, allowing designers and clients to understand the impact these

differing systems will have on the building’s performance and aesthetics.

With the ability to quickly and easily model and study any design, the possibilities are limitless.






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Design Elements

In order to communicate ideas to

shading system manufacturers, it is

important to know the terminology

associated with such systems.

In its simplest form, an exterior

shading system consists of an

outrigger, some type of blade or

multiple blades, possibly a fascia,

and mounting brackets.

The element that is most prominent

are the blades. They are performing

the shading and providing the

greatest visual impact.






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Blades

Blades come in many shapes and

sizes, widths, and span capabilities.

Finishes are generally a powder

coating on aluminum and are

available in an almost infinite

number of colors and even in

several “woodgrain” powder

coatings. There are other materials

available such as acrylic, wood,

laminated glass, and stone veneers.

Some variety of blades even have

LED lighting systems integrated into

the blades.






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LED Blades

LED lighting is changing the way we light our

buildings. The benefits over conventional types

of lighting are well documented. One significant

advantage is the flexibility in application. In

shading systems, the potential is only limited by

the designer’s imagination.

LED lighting being implemented in blades as

way marking or way finding elements on

buildings is an example of an imaginative and

practical use of the LED blades.

Here, they are working effectively on a hospital

building showing where the entrance is.






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Twisted Blades

One architectural trend is to create the illusion

of movement on building facades. In the past,

this effect was achieved by mounting blades on

building exteriors at different angles. One

manufacturer has taken a more innovative

approach by creating a sunshade system with

twisted blades that replicate waves.

Twisted sunshades are custom extruded metal

blades with a constant twist throughout. These

blades can be mounted so that they fully turn,

creating an illusion of building movement.






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Outriggers

The element responsible for holding

the blades is the outrigger. Outriggers

are fastened to either the curtain wall

framing, the building wall system, or

through some cable support

mechanism.

Generally, outrigger components are

plate aluminum. They are produced

using a computer numerical control

(CNC) mill. Whatever shape you draw

can be cut out on a CNC machine. This

offers the designer flexibility in terms of

satisfying aesthetic and functional

requirements.

Tapered Box Wedge

Tapered Box Trellis






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Fascia

Often with sun control systems, a

fascia element is added to the

outermost portion of the

assembly.

Not all systems require or use a

fascia, but it is one more element

to afford the complete

customization of the shading

system. As with blade elements,

fascia come in a multitude of

profiles and finishes.

Round Rectangular Bullnose Wedge

Fascia Tube Fascia Fascia Fascia






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Infill Components

An option that can be used in

place of blades is an infill shading

component. Essentially, these are

usually geometric grilles. The cell

sizes of these grilles can be

manipulated to be either more or

less dense. What you end up with

is varying degrees of shading, and

they often create interesting

shadow effects on the building

itself.

The infill elements are attached to

the system usually with a framing

component, which is then

fastened to the outriggers.






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Infill Components

Another option available for infill

components is using perforated

panels.

A variety of patterns are available

and the level of filtration can be

adjusted based on the size and

spacing of the perforations.






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Solid Surface Fins

A unique option is solid surface fins.

Solid surface can be cut, shaped, and

thermoformed into a sunshade system

that conserves energy and reduces

heat and glare, while adding

architectural excitement to building

exteriors.






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Cable-Supported Systems

An interesting and less common

system that can be used for shading is

a cable-supported system. There is an

opportunity for a unique aesthetic here.

An outrigger, either on the roof or

attached to the wall, sits above and

below a window system. The system is

similar to a venetian blind, the main

difference being the blades and cables

are static.

One advantage of this system is that it

is possible to shade the glazing

independent of the glazing’s structure.

This system lends itself well to retrofit

conditions.






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Quality Standards

One important consideration when choosing a shading system is

quality standards.

Be sure to specify that all components are manufactured utilizing

quality aluminum with PVDF finishes. For powder coat finishes, be

sure to use environmentally responsible products. Some are available

that have no volatile organic compounds (VOCs).

“Woodgrain” finishes can be applied using a special powder coat

method to emulate several wood types. Stainless steel fasteners

should be specified that can provide an allowance for the adjustment

of the system at the mounting condition, which will allow for minor

variances in the curtain wall or façade.

Also, always specify an engineered sun control system and hardware

whenever possible. Cutting corners here may be more costly in the

long run. In this photo, it is evident that the shading system was not

engineered.






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Quality Standards

Another aspect of quality standards to watch out for in shading systems is

how the blades are fastened to the outriggers.

Generally, there are two types of fastening methods: welded and

mechanical. Initially, it is usually less expensive to use welded

connections. However, there are other things to consider. Aesthetically,

mechanical connections are more attractive and the look is much cleaner.

Another advantage of mechanical connections is future maintenance.

Should a blade be damaged, the mechanically fastened element is easily

replaced, whereas the welded elements will likely require the entire

assembly to be replaced.

This is why it is important to have language in your specifications stating

that welded connections are unacceptable.

You can see here in the side-by-side comparison that the mechanical

connections are cleaner in terms of appearance.






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Engineered Systems

Designers will spend a considerable amount of time getting all of the

shading system’s elements to look and perform just right. However, it

is important to confer with a sun control system manufacturer during

the design phase.

Manufacturers have the needed expertise to look at not only the solar

control provided, but also wind and snow loads, and they can help

size the blades correctly for the spans shown.






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Engineered Systems

Wind and snow loads will impact the final design of the sun control assembly.

The sun control device manufacturer will use local climate data to perform the

necessary calculations and arrive at the imposed wind and snow loading on the

sun control assembly.

These calculations determine if blade spans or sizes are acceptable or not.

Discovering this information early in the design phase provides the designer

with an accurate picture of the device needed and helps prevent redesigns later,

saving time and money.






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Specifying Engineered Systems

A system that is not engineered may not include all considerations in its design, and responsibility for failure of the

system may fall to the architect. A well-written specification, involvement of the manufacturer, and an engineered system

minimize risk of future problems.

When specifying sun control systems, ensure the specification language requires manufacturers to support their designs

with engineering calculations. This will mostly impact blade deflection and failure under wind and snow loads.






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Building Connections

For sun control systems, there are different types of

connections to the building. Sun control manufacturers

generally attach to either the curtain wall or the wall itself.

More and more, we are seeing steel support structures

outboard from the building that are supporting the shading

system.

Typically, there is some type of T-bracket that is made for the

specific curtain wall mullion or wall condition. The shading

outriggers are then bolted to the T-brackets with adjustable

type hardware.

The T-brackets may be supplied by the sun control

manufacturer or the steel subcontractor.Various T-bracket

mounting conditions






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Building Connections: Movement

One critical calculation that must be considered for

any sun control system is movement. Failing to

design for movement can have devastating

effects.

Movement can be caused either seismically or

thermally. Seismic forces can cause the building to

experience story drift, which is a type of horizontal

shifting of the structure. Thermal movement occurs

when different parts of the shading system are

heated or cooled at different rates as a result of

various sun or weather phenomena.

Manufacturers engineer their products to withstand

these types of movements sometimes by providing

larger fastener openings and tolerances in

connections. This also accommodates field

adjustments for on-site discrepancies.






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Review Question

What factors should the designer keep in mind when designing sun shading?






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Answer

Sun shading requires both aesthetic and functional performance. Some key factors the designer should keep

in mind are:

• Wind and snow loads (request engineering calculations from manufacturer during design phase)

• Seismic and thermal movement of shading assemblies

• Solar orientation, project latitude and longitude (use computer modeling for accuracy)

• Blade or infill shading component design

• How the sun shading is to be attached—to the building structure or the curtain wall






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Design Strategies






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Aesthetics

Cantilevered Tube Blade Sun Control Cantilevered Demi-Fin Sun Control

Cantilevered sunshades are suited

for installations where loads from

wind and snow need to be

distributed over a larger area and

back to the building’s structural

support system.

Please remember the test

password SHADE. You will be

required to enter it in order to

proceed with the online test.






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Aesthetics

Vertical Airfoil Blade Sun Control (with Segmented

Curve)

Cantilevered Vertical Air Foil Blade Sun Control

(with Stretch Form Radius)

Vertical blade sunshades are

the most effective sunshade

for east and west elevations,

where low sun angles make

sun control challenging.






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Aesthetics

Perforated screens give superb daylight management while still allowing beautiful dappled light to filter in, creating

stunning visual effects.






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Aesthetics

Vertical Air Foil Blade Sun Control






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Aesthetics

Vertical Air Foil Blade on Alligator Casting Sun ControlVertical Screen Sun Control with Airfoil Horizontal Blades






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Aesthetics

Cantilevered Perforated Sheet Sun Control






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Aesthetics

Vertical blades and fins Vertical Blade Sun Control

with LED Accent Blades






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Aesthetics

Suspended Shade Sun Control

(tied to wall by diagonal supports)

Suspended Shade Sun Control

(tied to structure by diagonal supports)






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Aesthetics

Shade Canopy with Steel Structure and Shading Infill Modules






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Light Shelves






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Interior Benefits

To this point, our discussion has focused on the benefits of

adding shading systems to control solar heat gain while still

allowing unobstructed views to the outside.

There are many benefits to bringing natural light into the

interior; however, both heat and glare have to be considered.

When controlled, daylighting can potentially reduce energy

needs for lighting and improve occupants’ comfort levels. This

requires a system that will control sunlight from adversely

affecting occupants, while redirecting it deeper into the interior

to improve general illumination and reduce the need for

artificial lighting.

How can we do this? We need to turn our attention inward.






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Light Shelves

An effective method for bringing light in while keeping occupants

comfortable is to implement a light shelf in the interior in concert with

the external shading system.

The main purpose of a light shelf is to reflect sunlight deeper into the

building, and up towards the ceiling. A successful light shelf will

reduce glare at the window and provide natural light deeper into the

interior.

By locating the light shelf between the vision and transom panels of

the glazing, the exterior sun control system blocks the direct light

from entering the vision glass, while the light shelf redirects the light

entering through the transom panels upwards and deeper into the

space.

When we combine the exterior sun control device with an interior

light shelf, we can realize the maximum benefit of both systems.






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Light Shelf Location

The use of light shelves is part of bringing daylight

into a building and one strategy for meeting the

requirements for the Daylight credit in LEED v4.

These elements help reduce solar heat gain,

improve occupants’ comfort, and increase general

illumination through daylighting. This will also

reduce energy consumption from artificial lighting.

Generally, a light shelf should be located on the

same plane as the external horizontal shading

element, which is at the top of the vision portion of

the glazing (around 90 inches). The transom

glazing above this level is where we can harvest

daylight and reflect it deeper into the interior.

Ideally, the depth of the light shelf should be equal

to the height of the transom glazing for maximum

benefit.






< >

Light Shelf Material

For optimum effectiveness, light shelves need to

have the proper finish. Although a light shelf could

be constructed using drywall, it isn’t an ideal

material. The material would not stand up to

repeated cleaning, especially using harsh cleaning

solutions, so the surface would break down in a

short period and need frequent replacing.

Ideally, the material needs to be durable and highly

reflective. Also, the top surface needs to be

accessible for cleaning as it tends to accumulate

dust if left untended. Some light shelf systems have

built-in mechanisms allowing for the shelf to be

lowered on a hinge for easy access and cleaning.






< >

Light Shelves

The combination of a

thoughtful exterior sun control

system and an interior light

shelf can reduce energy loads

for HVAC and lighting needs

while increasing occupants’

visual and thermal comfort by

promoting daylighting,

preserving views, and reducing

solar heat gain.






< >

Review Question

How should interior light shelves integrate with exterior shading devices?






< >

Answer

The purpose of exterior shading is to prevent direct light from entering the glazing. The purpose of an interior

light shelf is to redirect light that has passed through the glazing up to the ceiling (to reduce glare) and deeper

into the space (to maximize useful daylighting and reduce use of artificial lighting).

The best strategy is to divide the glazing into vision glazing below and a transom above. A horizontal exterior

shading device and interior light shelf should be aligned between the vision panel and transom panel. Daylight

from the transom window will be harvested and reflected towards the ceiling. Direct light will be blocked from

the vision panel.

This coordinated solution will minimize solar gain while maximizing daylighting.






< >

Summary






< >

Summary

As mentioned at the outset, we need to act now in order to prevent irreversible damage to the environment caused by

GHG emissions. Currently, buildings are responsible for roughly half of the energy used in the U.S. and across the globe.

It is possible to change this. Through the implementation of innovative technologies and thoughtful design strategies, we

can change buildings into a central part of the solution. Some of those strategies include the following:

• Implementing sun control systems as part of the design process from the early stages of development

• Modeling the effectiveness of various design strategies and their ability to reduce the building’s need for energy while

improving the building’s interior environment

• Demonstrating and validating the benefits through improved occupant comfort, which also demonstrates the potential

for a positive ROI (return on investment)

• Considering the structural needs of the shading system early in the process and ensuring long-term system integrity

by specifying engineered systems






< >

Conclusion

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A Sustainable Design Practice