BUILDING ENERGY - Fall 2016 - 35


FIGURE 2: EXAMPLE OF RAINSCREEN STUDY SHOWING INTENDED DETAIL AND R-VALUE, AS WELL AS THE
R-VALUE OBSERVED FROM A THERMAL IMAGE AND THROUGH THE HEAT-FLOW SIMULATION.

FIGURE 3: THREE THERM SIMULATIONS FOR
DISCONTINUOUS THERMAL BRIDGES (RIP-8.5).

Because these simplified, singledimension calculations do not account
for any thermal bridging, they were
used as the "baseline R-value" as the
best-case scenario.
A thermal imaging camera was
used to determine the actual R-value
of existing façades. Teams were
deployed to 15 buildings to assess the
general envelope thermal performance
and scan for areas that appeared
to perform differently. Using the
methodology published by Madding
(2008), the exterior air temperature,
interior air temperature and the radiant
temperature were gathered using
infrared imaging and temperature data
loggers in order to calculate the as-built
R-value of the assembly (see figure 2).
Because physically altering the built
conditions was not possible, computer
simulations were used to test possible
improvements to various construction
details. Lawrence Berkeley National
Laboratory's THERM 7.3 program was
employed to determine R-values of
complete assemblies, including thermal
bridges, based upon its ease of use

and ability to integrate into the design
process. For each detail, models were
prepared of the constructed designs
and were then calibrated by comparing
them to the actual performance
measured in the field with the thermal
imaging camera. For discontinuous
thermal bridges, such as bolts or clips,
two methods were used to account
for their three-dimensional impact:
the parallel path method and the
isothermal planes method.
The parallel path method takes a
weighted average of two simulations,
one with the discontinuous bridging
element and one without it. The
isothermal planes method runs
one simulation using a weighted
conductivity of the bridging material
and insulation for the discontinuous
thermal element. Because the
parallel path tends to overestimate
the impact of the thermal bridging,
and the isothermal planes tends
to underestimate the impact, both
methods were used to understand the
range of impact the thermal bridge
might have (see figure 3).
CONTINUED ON PAGE 37

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Table of Contents for the Digital Edition of BUILDING ENERGY - Fall 2016

From the Executive Director and Board Chair
New York City is Transforming Buildings for a Low Carbon Future
Does Electric Grid 2.0 Mean Energy Democracy?
Resiliency for Affordable Multifamily Housing: What We Have Learned and What We Still Need to Know
Break It or Lose It: Thermal Bridging in Rainscreen Systems
My PEI is Better Than Your PEI
Life Cycle Assessment at the Speed of Design
From Theory to Reality: Our Journey Toward Sustainability Building a Net Zero Home
Solar Policy in the Northeast: What’s New, What’s Next?
BuildingEnergy Green Pages
Index to Advertisers / Ad.com
BUILDING ENERGY - Fall 2016 - cover1
BUILDING ENERGY - Fall 2016 - cover2
BUILDING ENERGY - Fall 2016 - 3
BUILDING ENERGY - Fall 2016 - 4
BUILDING ENERGY - Fall 2016 - 5
BUILDING ENERGY - Fall 2016 - From the Executive Director and Board Chair
BUILDING ENERGY - Fall 2016 - 7
BUILDING ENERGY - Fall 2016 - 8
BUILDING ENERGY - Fall 2016 - 9
BUILDING ENERGY - Fall 2016 - New York City is Transforming Buildings for a Low Carbon Future
BUILDING ENERGY - Fall 2016 - 11
BUILDING ENERGY - Fall 2016 - 12
BUILDING ENERGY - Fall 2016 - 13
BUILDING ENERGY - Fall 2016 - 14
BUILDING ENERGY - Fall 2016 - 15
BUILDING ENERGY - Fall 2016 - 16
BUILDING ENERGY - Fall 2016 - 17
BUILDING ENERGY - Fall 2016 - 18
BUILDING ENERGY - Fall 2016 - 19
BUILDING ENERGY - Fall 2016 - Does Electric Grid 2.0 Mean Energy Democracy?
BUILDING ENERGY - Fall 2016 - 21
BUILDING ENERGY - Fall 2016 - 22
BUILDING ENERGY - Fall 2016 - 23
BUILDING ENERGY - Fall 2016 - 24
BUILDING ENERGY - Fall 2016 - 25
BUILDING ENERGY - Fall 2016 - Resiliency for Affordable Multifamily Housing: What We Have Learned and What We Still Need to Know
BUILDING ENERGY - Fall 2016 - 27
BUILDING ENERGY - Fall 2016 - 28
BUILDING ENERGY - Fall 2016 - 29
BUILDING ENERGY - Fall 2016 - 30
BUILDING ENERGY - Fall 2016 - 31
BUILDING ENERGY - Fall 2016 - 32
BUILDING ENERGY - Fall 2016 - 33
BUILDING ENERGY - Fall 2016 - Break It or Lose It: Thermal Bridging in Rainscreen Systems
BUILDING ENERGY - Fall 2016 - 35
BUILDING ENERGY - Fall 2016 - 36
BUILDING ENERGY - Fall 2016 - 37
BUILDING ENERGY - Fall 2016 - 38
BUILDING ENERGY - Fall 2016 - 39
BUILDING ENERGY - Fall 2016 - My PEI is Better Than Your PEI
BUILDING ENERGY - Fall 2016 - 41
BUILDING ENERGY - Fall 2016 - 42
BUILDING ENERGY - Fall 2016 - 43
BUILDING ENERGY - Fall 2016 - Life Cycle Assessment at the Speed of Design
BUILDING ENERGY - Fall 2016 - 45
BUILDING ENERGY - Fall 2016 - 46
BUILDING ENERGY - Fall 2016 - 47
BUILDING ENERGY - Fall 2016 - From Theory to Reality: Our Journey Toward Sustainability Building a Net Zero Home
BUILDING ENERGY - Fall 2016 - 49
BUILDING ENERGY - Fall 2016 - 50
BUILDING ENERGY - Fall 2016 - Solar Policy in the Northeast: What’s New, What’s Next?
BUILDING ENERGY - Fall 2016 - 52
BUILDING ENERGY - Fall 2016 - 53
BUILDING ENERGY - Fall 2016 - BuildingEnergy Green Pages
BUILDING ENERGY - Fall 2016 - 55
BUILDING ENERGY - Fall 2016 - 56
BUILDING ENERGY - Fall 2016 - 57
BUILDING ENERGY - Fall 2016 - 58
BUILDING ENERGY - Fall 2016 - 59
BUILDING ENERGY - Fall 2016 - 60
BUILDING ENERGY - Fall 2016 - 61
BUILDING ENERGY - Fall 2016 - 62
BUILDING ENERGY - Fall 2016 - 63
BUILDING ENERGY - Fall 2016 - 64
BUILDING ENERGY - Fall 2016 - 65
BUILDING ENERGY - Fall 2016 - 66
BUILDING ENERGY - Fall 2016 - 67
BUILDING ENERGY - Fall 2016 - 68
BUILDING ENERGY - Fall 2016 - 69
BUILDING ENERGY - Fall 2016 - 70
BUILDING ENERGY - Fall 2016 - 71
BUILDING ENERGY - Fall 2016 - 72
BUILDING ENERGY - Fall 2016 - 73
BUILDING ENERGY - Fall 2016 - 74
BUILDING ENERGY - Fall 2016 - 75
BUILDING ENERGY - Fall 2016 - 76
BUILDING ENERGY - Fall 2016 - 77
BUILDING ENERGY - Fall 2016 - 78
BUILDING ENERGY - Fall 2016 - 79
BUILDING ENERGY - Fall 2016 - 80
BUILDING ENERGY - Fall 2016 - Index to Advertisers / Ad.com
BUILDING ENERGY - Fall 2016 - 82
BUILDING ENERGY - Fall 2016 - cover3
BUILDING ENERGY - Fall 2016 - cover4
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