2016.05.19 CSI Richmond - Intertek BECx and Building Enclosure Design2
1. Keith P. Nelson, AIA
Senior Project Architect
May 19, 2016
Building Enclosure
Commissioning (BECx)
Provider: Intertek
Provider Number: 404108121
Course Number:
2. 2
Credit(s) earned on completion of
this course will be reported to AIA
CES for AIA members.
Certificates of Completion for both
AIA members and non-AIA
members are available upon
request.
This course is registered with AIA
CES for continuing professional
education. As such, it does not
include content that may be
deemed or construed to be an
approval or endorsement by the
AIA of any material of construction
or any method or manner of
handling, using, distributing, or
dealing in any material or product.
_______________________________________
Questions related to specific materials, methods,
and services will be addressed at the conclusion
of this presentation.
4. Course Description
While commissioning of many building systems has been
around for many years, Building Enclosure Commissioning
(BECx) is relatively newer to the design and construction
industries. This presentation will provide a primer on the
practice of BECx and its benefits with real world case
studies and then dive further into the various approaches as
defined by industry standards and code.
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5. Learning Objectives
Upon completing the course participants will be able to:
1. Describe the general function and performance
requirements of the building enclosure
2. Describe the process of BECx with an understanding of
the potential value the process may bring to a project;
3. Describe the various stages of BECx and the
deliverables typically produced;
4. Identify the various codes and standards bodies that
have incorporated BECx into them; and
5. Identify and discuss the differences between the
application of BECx in the various standards and model
codes.
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8. What is the Building Enclosure?
Shelter
Security / Safety
8
9. What is the Building Enclosure?
Aesthetics
Performance
9
10. What is the Building Enclosure?
Durable / Maintainable
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11. What is the Building Enclosure?
Serviceable / Functional
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12. What is the Building Enclosure?
The primary function of the building enclosure is to separate the
interior environment from the exterior environment usually including
the following components:
• Roof
• Above grade walls
• Fenestration
• Below grade walls
• Base or Exposed Floor Systems
Enclosures may also include the separation between interior
spaces. The building enclosure may contain, but is not the same as,
the “Building Thermal Envelope” as defined by the IECC.
13. What is the Building Enclosure?
13 ASHRAE 90.1-2013
22. Hygrothermal Analysis
The study of a system involving coupled heat and moisture
transfer. The purpose of hygrothermal analysis is usually to
provide sufficient and appropriate information needed for
decision –making. The three most common reasons for
conducting hygrothermal analysis can be defined as:
1. To Learn- Develop an appropriate level of understanding of enclosure response,
e.g. does condensation occur; it thermal bridging significant relative to condensation
or excessive moisture accumulation.
2. To Design- Identification and/or avoidance of a performance concern: moisture
accumulation, condensation, corrosion, and mold.
3. To Comply- It is becoming more common for AHJ’s, owners, or governing bodies to
require hygrothermal analysis.
What is the Building Enclosure?
23. Control Layers
Building Enclosures are designed to control
multiple loadings this presentation will primarily be
concerned with the following in order of importance:
1. Water Control Layer
2. Air Control Layer
3. Vapor Control Layer
4. Thermal Control Layer
What is the Building Enclosure?
24. Water Control Layer (Priority 1)
The continuous layer (comprised of one of several
materials and formed into planes to form a three
dimensional boundary) that is designed, installed, or acts
to control the passage of liquid water even after long or
continuous exposure to moisture.
• Interconnected with flashings, window and door
openings, and other penetrations
• Overlap each other shingle fashion or are sealed so
that water flow is downward and outward.
• Goal is to evacuate water from the assembly and away
from the building as quickly as reasonably possible.
What is the Building Enclosure?
25. Water-Resistive Barrier
A code (ICC/ASTM) specific term that is often used
interchangeably with Weather-Resistive Barrier.
What is the Building Enclosure?
26. Drainage Plane
Water repellent materials (building paper,
housewrap, foam insulation, etc.) which are
designed and constructed to drain water. They are
interconnected with flashings, window and door
openings, and other penetrations of the building
enclosure to provide drainage of water to the
exterior of the building. The materials that form the
drainage plane overlap each other shingle fashion
or are sealed so that water flow is downward and
outward.
What is the Building Enclosure?
27. Modes of Bulk Water
Transport
What is the Building Enclosure?
28. Air Control Layer (Priority 2)
Three-dimensional systems of materials designed,
constructed, and/or acting to control air flow across a building
enclosure, or between a conditioned space and an
unconditioned space. The pressure boundary of the enclosure
should, by definition, be coincident with the plane of a
functional air control layer system.
• Interconnected with flashings, window and door openings,
and other penetrations
• CONTINUITY IS CRITICAL
• Moisture-Laden-Airflow can carry 100 to 300x’s more
moisture than diffusion over the same time period.
• Least regulated within the building code
Variants: Air Barrier
What is the Building Enclosure?
29. Moisture Transport via Air v. via Diffusion
2/3 Pint via
Diffusion
50 Pints via Air
Flow
What is the Building Enclosure?
32. Vapor Control Layer (Priority 3)
The component or components that are designed
and installed in an assembly to control the
movement of water by vapor diffusion.
• Vapor diffusion is a linear process of moisture
transport through a material
• “Continuity” of a Vapor Control Layer may be
significantly dis-continuous (10% +) and still
perform as a vapor control.
What is the Building Enclosure?
33. Water Vapor Permeability (perm inches)
the time rate of water vapor transmission through unit area of
flat material of unit thickness induced by unit vapor pressure
difference between two specific surfaces, under specified
temperature and humidity conditions.
Water Vapor Permeance (perms)
The time rate of water vapor transmission through unit area of
flat material or construction induced by unit vapor pressure
difference between two specific surfaces, under specified
temperature and humidity conditions.
Permeability (Perm inches) ÷ Thickness (inches) = perms
What is the Building Enclosure?
34. Vapor Retarder Class (IBC)
ASTM E96 Dry Cup Wet
Cup
What is the Building Enclosure?
36. Thermal Control Layer (Priority 4)
The component or components that are designed and
installed in an assembly to control the transfer of thermal
energy (heat). Typically these are comprised of insulation
products, radiant barriers, or trapped gaps filled with air or
other gases.
• Interrupted by flashings, window and door openings, and
other penetrations
• Understand the Impact of Thermal Bridging (see ASHRAE
90.1- Appendix A)
Variants:
Thermal Envelope, Insulation Layer
What is the Building Enclosure?
37. 2015 IECC & IRC Climate Zone Map
What is the Building Enclosure?
44. WH-ETL Mark
Definition: Process that verifies
enclosure performance against the
Owner’s Project Requirements
(OPR) and Basis of Design (BOD)
• BECx standards:
– ASTM E2318
– CSA Z 320
– ASHRAE 202
– VDI 6055
Formalization of building envelope
consulting practice
What is BECx?
45. What is BECx?
“Building Enclosure Commissioning (BECx) is
a process that begins with the establishment of
the Owner’s Project Requirements (OPR) and
endeavors to ensure that the exterior
enclosure and those elements intended to
provide environmental separation within a
building or structure meet or exceed the
expectations of the Owner.”
46. What is BECx?
ASTM E2813-2012: “Building
Enclosure Commissioning
(BECx) is a process that begins
with the establishment of the
Owner’s Project Requirements
(OPR) and endeavors to ensure
that the exterior enclosure and
those elements intended to provide
environmental separation within a
building or structure meet or
exceed the expectations of the
Owner.”
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47. Time
CostQuality
Early Project Learning
-Design / Model Reviews
-Minimize Delays
-Tested Mock-ups
Process Pays for Itself
-Minimize Change Orders
-Early Failure Identification
-Reduces Risk/Call Backs
Value Based Service
-Minimize Errors
-Verifies Performance
-End User Focus
WH DLP
What is BECx?
51. 51
Process that verifies enclosure
performance against the
Owner’s Project Requirements
(OPR) and Basis of Design
(BOD)
BECx:
• Formal Process (start to
finish)
• Based on performance
• More accountability
• Based on real world
conditions
Enclosure Consulting:
• Could be only one task
• Based on reducing
liability
• Less accountability
• Based on standards
What is BECx?
53. Pre-Design Phase
Owner Project Requirements
Basis of Design
Documents the concepts, calculations, decisions, and
product selections used in the design to meet the OPR
Initial BECx Plan
Project schedule inclusive of BECx tasks and milestones
and Roles and responsibilities of commissioning team
members.
Establishing the Owner’s Project
Requirements relative to the enclosure
performance.
60. Design Phase
• Incorporate BECx requirements into construction documents
– BECx Specification
– FPT Specification
• Design Reviews
• Update OPR and BECx Plan
Compliance with the Owner’s Project Requirements evaluating
design based on experience.
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63. Credit: Journal of Building Enclosure Design Summer 2011 “Improvement of Air
Tightness in U.S. Army Buildings” pgs. 11-13
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Design Phase
64. Control Layers
Building Enclosures are designed to control
multiple loadings this presentation will primarily be
concerned with the following in order of importance:
1. Water Control Layer
2. Air Control Layer
3. Vapor Control Layer
4. Thermal Control Layer
Design Phase
65. 65
Make sure we are sealing to
the air barrier...but also make
sure to tie-in with the primary
seal line of the curtain
wall/window system.
Understand that this is
a relatively new
concept for many
trades.
Design Phase
70. Construction Phase
• BECx Kick Off meeting
• Submittal Review
• Pre-Construction Meetings
• Mockup Construction and Testing
• Other
– RFI, ASI, CCD Review
– Change Order Review
– Substitution Request Review
– Value Engineering Review
Compliance with the Owner’s Project Requirements and the Contract
for Construction.
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73. Construction Phase
• Verify the performance of
the systems
• Set construction standards
• Establish sequencing of
work
• Verify material selection
Learning
Value of Mockups
74. Construction Phase
• Complete waterproofing system
• Interface of wall to roof condition
• Typical wall and roof penetrations
• A sample of cladding anchorage
• Typical fenestration assemblies
• Constructed to be air tight to facilitate testing
Mockups Generally Include
75. Construction Phase
Types of Mockups
• Laboratory
• On-site Off-Building
• On-Site On-Building (First
Installation)
79. Functional Performance Verification
• Verify the performance of the systems
• Verifies installation methods
Avoid late stage (expensive)
problems with early detection.
81. Functional Performance Verification
Common Test Methods
• Air Infiltration
– ASTM E783
– ASTM E1186
– ASTM E779
• Water Penetration
– ASTM E1105
– AAMA 501.1
– AAMA 501.2
• Other
– ASTM D4541 (Adhesion)
82. ASTM E783
• Field Measurement of Air Leakage Through Installed Exterior
Windows and Doors
• Quantitative Air Infiltration Test
Functional Performance Verification
83. ASTM E1186
• Standard Practices for Air Leakage Site Detection in Building
Envelopes and Air Barrier Systems
• Qualitative Air Infiltration/Exfiltration Test
Functional Performance Verification
84. ASTM E779 (Whole Building Air Test)
• Standard Test Method for Determining Air Leakage Rate by Fan
Pressurization
• Quantitative Whole Building Air Leakage Test
Functional Performance Verification
85. ASTM E1105
• Standard Test Method for Field Determination of Water Penetration
of Installed Exterior Windows, Skylights, Doors, and Curtain Walls,
by Uniform or Cyclic Static Air Pressure Difference
• Water Penetration Test
Functional Performance Verification
86. AAMA 501.1
• Standard Test Method for Water Penetration of Windows, Curtain
Walls, and Doors using Dynamic Pressure
• Water Penetration Test
Functional Performance Verification
87. AAMA 501.2
• Quality Assurance and Diagnostic Water Leakage Field Check of
Installed Storefronts, Curtain Walls and Sloped Glazing Systems
• Water Penetration Test
Functional Performance Verification
88. ASTM D4541
• Standard Test Method for Pull-Off Strength of Coatings Using
Portable Adhesion Testers
• Quantitative Adhesion Test
Functional Performance Verification
89. E779 Whole Building
Air Test (WBAT)
• Quantitative air leakage
test
• Measures the air
tightness of the building
enclosure
• Controlled pressurization
and depressurization
Functional Performance Verification
90. The Purpose of the
WBAT
• Validation of installation
• Verify compliance with
performance requirements
Reducing air leakage rate can result in up to
35% heating energy cost savings.
National Institute of Standards and Technology Interagency Report (NISTIR) 7238 by Emmerich, McDowell, and
Anis
Functional Performance Verification
95. Post-Occupancy Phase
• Final BECx record
• Enclosure maintenance schedule
• 10-month post-occupancy observation
(warranty)
96. What is not BECx?
• Water penetration testing…
• A whole building air test
• Consulting / design assistance
• The contractors QC program
• A review of the thermal envelope
• Full time inspection
• Post occupancy thermal scan
• A checklist…
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97. Owner’s Response…
“Don’t I already pay for this through the Design and
Construction Contracts?”
• The vast majority of construction claims are due to
enclosure failures, i.e. water leakage.
• It is estimated that 85% or more of claims for water
leakage occur at the interface of systems, i.e. window to
wall; wall to roof; etc.
• Often these interface conditions land in the space
between subcontracts, “by others”.
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101. Current Efforts
• NIBS/BETEC BECx Certificate
• ASTM E06 Standard and Guideline
• ASHRAE 90.1/189.1 Increasing Requirements
• LEED Increasing Requirements
• ISO Standard to be Proposed
• …many others…
Everyone is not working from the same playbook…
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102. Why BECx?
Building Performance
• Water Control
• Air control
– HVAC system performance/size selection
– Moisture control
Comfort
Above Code Certification (LEEDv3 v4)
Mandatory (ASHRAE 90.1-2013 Add L / ASHRAE 189.1)
Others???
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117. Take Away
• Building Enclosure performance is important and
complicated.
• BECx is a complete process focus on meeting the
documented need of the project through the OPR.
• BECx can take many forms and is difficult to standardize.
• There are a variety of performance verification tools
available to meet the need of the project.
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118. Keith P. Nelson, Architect
Keith.Nelson@intertek.com
804.869.4617
icenter@intertek.com
www.intertek.com/building
This concludes The American Institute of
Architects Continuing Education Systems Course
129. Keith P. Nelson, Architect
Keith.Nelson@intertek.com
804.869.4617
icenter@intertek.com
www.intertek.com/building
This concludes The American Institute of
Architects Continuing Education Systems Course
