Group 4.C - Skylights 1-3: Introduction to Skylights for Daylighting of Buildings Flashcards
1. Using Skylights for Day-lighting of Buildings 2. The Skylighting System 3. Daylighting Design
Daylight impacts human biological responses and vision. T or F
T.
Some health benefits of daylighting include:
Hint: SVD SAM
SAD reduction Visual Clarity D - Aids in Vitamin D production Sleep patterns improved - Pineal gland Alertness Mood improved
Unit skylights are defined as
Complete factory-assembled fenestration unit of not more than one panel of glass or plastic.
(…installed on a sloped or horizontal orientation primarily for daylighting)
How have skylights (daylighting) been shown to improve student performance in classrooms.
20% higher standard math tests score
26% higher reading scores
Two main strategies for incorporating daylight are:
Side lighting
Top lighting
What is the difference in natural light distribution between side-lighting and top-lighting?
Side-lighting distribution is more abundant closer to the window or light shelf. Top lighting (skylights) can spread light more evenly in a space.
In commercial buildings in the US, what % of floor area is directly below a roof? What does this mean?
60%
60% of U.S. commercial floorspace could benefit from unit skylights.
What does the term “foot candle’ refer to?
The illumination produced by a source of one candle at a distance of one foot.
Equal to one lumen/s.f.
The sky is ___ times brighter straight-up than on the horizon, even on a cloudy day.
Three times.
How much illumination (f.c.) is provided by direct sunlight and blue-sky (away from the sun)
5,000 - 10,000 f.c.
1,000 - 3,000 f.c.
What entity provides recommended illuminance levels for various spaces and uses?
Illuminating Engineering Society (I.E.S)
List the IES recommended illuminance levels (f.c. / l/s.f.) for each space: Warehouse Classroom Retail General Office Library Manufacturing
5-30 l/sf 20 - 50 20 - 50 20 - 50 30 - 50 30 - 75
In a top-lighting context, is building orientation a critical factor?
No.
Unit skylights receive direct sunlight all day long. .
In designing skylighting system some building characteristics to consider include:
Ceiling Ht.
Color of surfaces
Shelving
Partitions.
A properly designed skylighting system works in conjunction with what other building system?
Why?
Automatic lighting controls.
To allow reduction of artificial lighting as daylight levels increase.
In what 4 ways have modern skylights addressed water intrusion issues from site-built skylight assemblies?
Better, factory formed components
Improved gaskets and sealants
Condensation containment
Thermally-broken frame
What standard provides guidelines for effective skylight installation.
AAMA 1607
Cite examples of what aspects of a skylight system are strategically typically considered in the design?
Skylight aperture
Light well
Light well depth
What general aspects of skylight performance are impacted by material selection?
(Hint: DALE)
D Durability
A Amount of Visible light
L Light Diffusion
E Energy Performance
List some glass material options for skylights in terms of glass material quality and surface treatments
Glass:
Quality: Tempered, Laminated
Treatment: Low-E coated, Sand Blasted or chemically etched, Ceramic frit
List 5 plastic and polymer material options for unit skylight lenses:
PAFIM CI
PolyCarbonate Acrylic Fiberglass Insulated panel Molded sheet Co-polyester Impact Modified
List factors that must be considered in evaluating glazing materials:
Visible Transmittance
Haze Factor
SHGC
U-factor -thermal conductance
What does haze factor refer to
The ratio of diffusely transmitted light (>2.5 deg of scatter) to the total transmitted light of a glazing material.
What are NAFS requirements regarding haze?
What standard is referenced?
Max allowed scatter of original light transmittance: 10%
ASTM D1003
Additional considerations in skylighting design (Beyond unit skylight materials) include:
Hint (DWUGS)
(U is a verb…)
Diffusion of light Well design Utilize light-colored surfaces Glare avoidance Size and Spacing of skylight
Why is clear glazing not ideal for skylights?
It creates ‘hot spots’ that travel across the floor
Ways to achieve diffusion and control beam sunlight include:
try for 4 of 6
Glazing properties louvers well shape well diffusers banners shades