High Performance Building Design
CIV_ENV 395 Week 4: Comfort & Façade Design
October 9, 2017
Comfort
• Visual Comfort
• Thermal Comfort
http://www.archdaily.com/773066/search-ends-for-solution-to-museum-towers-glare-problems-at-nasher-sculpture-center
http://www.archdaily.com/773066/search-ends-for-solution-to-museum-towers-glare-problems-at-nasher-sculpture-center
Image Credits: Nicole L. Peterson
Supplemental blinds were
added in front of perimeter
office space after occupancy
Daylight Analysis
Image Credits: Nicole L. Peterson, The space between research and practice: A critical evaluation of computer-based lighting metricshttp://dmg.caup.washington.edu/pdfs/Thesis.NicolePeterson.2015.pdf
Gla
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ics
Comfort
• One way to achieve visual AND thermal
comfort is external shading
• What about internal shading?
• How do we optimize this?
Sun Path Diagrams
Sun Path Diagrams
Sun Path Diagrams
Months
Sun Path Diagrams
Analemma:
Hour
Sun Path Diagrams
Sun
Altitude
Sun path diagram
Building Façade Shading Cut-off AnglesSouth façade at noon
Building Façade Shading Cut-off AnglesSouth façade at noon
h
June 21 @ noon: ?
September 21 @ noon: ?
December 21 @ noon: ?
x ?
Getting sun angles:
• Analog
• Ecotect
• Grasshopper + Ladybug
Rhino / Grasshopper plug-ins
Rhino / Grasshopper plug-ins
Hammer vs. Swiss Army Knife
Ladybug
Ladybug
Ladybug
http://www.grasshopper3d.com/group/ladybug
Links:
• Ladybug homepage:http://www.grasshopper3d.com/group/ladybug
• Intro video series by MostaphaRoudsari:https://www.youtube.com/watch?v=9_u0dnyq2QI
• Intro video series by Chris Mackeyhttps://www.youtube.com/watch?v=8UFkJL-aZy8
• Ladybug video seminar: https://vimeo.com/ondemand/performancenetwork/180282919?autoplay=1
Ladybug
https://hydrashare.github.io/hydra/
LadybugSearch!
Building Façade Shading Cut-off AnglesSouth façade at noon
h
June 21 @ noon: ?
September 21 @ noon: ?
December 21 @ noon: ?
x
• Which timeframe is shading necessary?
e.g. summer only? + some shoulder seasons?
• Solve for overhang depth, x
(or solve for h if you know what you want x to be)
• Think about your climate, program, what proportions
make sense, window head heights, etc.
• Remember: this is only for the South façade
• We use this as a starting point, and then move to
analysis to understand the daylight and glare
conditions inside
Trigonometry + Excel:
tangent = opposite
adjacent
tan = h
xx =
h
tan
Building Façade Shading Cut-off AnglesSouth façade at noon
h
June 21 @ noon: ?
September 21 @ noon: ?
December 21 @ noon: ?x ?
Maybe you have horizontal louvers
rather than an overhang -> shading masks
Building Shading
Remember these rules of thumb:
This is not just for visual comfort, but also
for thermal comfort. Remember – external
shading blocks solar gains from the façade.
We will talk more about thermal comfort
next class.
Solar Radiation Maps: Example
Solar Radiation Maps: Demo
What about our building,
2020 Ridge?
Solar Radiation Maps: Demo
N
Solar Radiation Maps: Demo
But what does this mean?
This is for you to figure out in your homework.
Remember to always include a legend with units / north arrow – it is meaningless without it !
Use an appropriate scale to show a gradient & differences between façades.
Overshadowing: Example
Shadow Studies: Example
Façade design
Where do you want to place windows based on orientation, program, etc?
• Think about punched openings vs curtainwall
• Potential focused work: glass design, daylight simulations
Apple Store – New York City
http://www.apple.com/retail/fifthavenue/
David Zwirner Gallery – New York City
http://www.forbes.com/sites/tamarawarren/
2013/01/29/david-zwirner-opens-new-manhattan-gallery/
Glazing properties
• With better thermal insulation, it may be possible to have a higher glazing
percentage; U-value and WWR are tradeoffs that can be balanced to
achieve optimal overall energy performance.
• For cold climates: There are cases where triple glazing has eliminated the
need for perimeter heating. Better performing glass can also result in less
drafts.
• Think about how all of this comes together in low-E coatings, frit, glazing-
integrated PVs, and electrochromic glass.
Glazing properties: considerations
Glazing properties: considerations
Glazing properties: considerations
Assignment #4:
Comfort / Façade Design
Assignment #4: Façade / ShadingOverall goal:
Begin thinking about your façade design & what shading strategies you will implement.
1. Shading cutoff calculation
Perform a shading cutoff calculation with the method of your choice. Document it fully.
• If you were to implement horizontal shading elements on the south façade, how deep
would you make them and why?
• Are you planning for overhangs, lightshelves, louvers, a combination, or none of these?
2. Solar radiation map
Given the solar radiation results, display your findings in whatever format you like.
You must explain the following:
• Do you think our building’s orientation is optimal?
• Note the differences by façade and begin thinking about corresponding strategies. Each
façade should be represented using graphics & text (you can use axonometric views).
e.g. The north façade has an average solar radiation of 500 kWh/m2, and should be the target.
The West has an average solar radiation of 1200 kWh/m2, and we plan to use automated
venetian blinds to reduce it down to the target.
3. Based on 1 & 2, begin mapping out where you plan to have windows and what shading strategy you
will use. You can use whatever medium you like e.g. Rhino model, sketches, etc.