1. Evaluating Re-use of Existing Exterior Envelope
Re-skin vs. Renovate

2. • is a Registered Provider with The American Institute of Architects Continuing
Education Systems (AIA/CES). Credit(s) earned on completion of this program 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 program 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.
•In October 2010, the AIA/CES system was updated with the new CES Discovery
system, in that time we have transferred more than one million records. This new
update has made it necessary to remind us of the AIA/CES policies and procedures, to
introduce the “new” provider ethics, and to reintroduce the AIA/CES audits/quality
assurance program. This presentation covers those areas giving providers the
opportunity to give feedback and input.

3. Learning Objectives
At the end of this program, participants will be able to:
1) Will understand the typical service life of different cladding materials in the Texas
Gulf Coast area.
2) Will be able to identify critical failures of different cladding materials that indicate
replacement.
3) Will be able to calculate the life cycle implications of re-cladding vs. cladding repair.
4) Will be able to identify the potential energy impacts of replacing or maintaining a
building’s envelope.

4. The greenest
building is the one
that is already built.
Evaluation of Existing Structures

5. • Structural failure of façade or cladding
• Water intrusion
• Master Plan for long term Ownership
• New Ownership
Major Reasons to Review the Envelope

6. Step One - Investigation and Evaluation of Existing
• Owner
• Architect
• Building Envelope Consultant
• Structural Engineer
• MEP Engineer
• Project Manager or Broker
• Facilities Engineer

7. 5 Key Items
Structural Integrity
Thermal Performance
Permeance
Significance
Life Cycle
Good Condition Poor Condition
Good Performance Low Performance
Low Permeance High Permeance
Existing Image vs New Design
Short Life vs Long Term

8. Program, Design and Client Input
User Inputbuilding
envelope
M,C,R
Option 1
• re-glaze only
• conventional HVAC
• bldg. envelope repairs
T,D
Option 2
• modify precast:
raise header
• new vertical strip
curtainwall
• underfloor HVAC
Option 3
• remove all precast:
new unitized
curtainwall
• underfloor HVAC
Option 1
• re-glaze only
• conventional HVAC
• new arch. metal
at monitors
• new skylights
Option 3
• remove all precast,
new unitized curtainwall
• underfloor HVAC
• all new monitors & piping
Option 2
• remove precast below
brim, new curtainwall
• underfloor HVAC @ 1st fl,
conventional HVAC @ 2nd
• mods to monitors for daylight
amenities building
schematic design
T
C
Kirksey / WPM
renovated offices
8 Nov 2007
M
R
program
detail
WORKSuser list
Kirksey
D
Kirksey
amenities
building
Program, Design and Client Input – Building Use

9. Significance of façade
Historic
Tax credits or Federal $ - must comply with review
(Professional recommendation is the same)
Iconic
Represents Campus Identity or Owner History
Intangibles - Façade Value

10. •Change of Use
•5% increase of Lateral Load
•Improvements worth over 50% of Building Value
What triggers a code upgrade?
2012 IBC - Chapter 34 Existing Building Code
Energy Code Compliance
Code and standards

11. Code and standards
If the owner wants windstorm
insurance through
TWIA, evaluation and/or
upgrades may be required

12. Physical/Structural Characteristics of the
Building Envelope
Deficiencies in one or more of these areas
can lead the decision matrix for
recladding:
• Condition of Façade Materials
• Condition of Vertical Support Systems
• Performance of façade systems
Visual Inspection

13. • Document Review
• Visual Assessment
• Establish Monitoring
Investigative Techniques

14. Performance of façade systems
• Differential Movement
• Displacement
• Cracking
Control of water
• Plugged weepholes
• Malfunctioning downspouts
• Improper flashing
Visual Inspection

15. • Condition of Vertical Support Systems
Shelf angle
Lintels
Panel support clips
Typical distress conditions
• Corrosion
• Cracking
• Displacements
Visual Inspection -

16. (Natural Stone, Cast Stone, Brick, Terra Cotta)
Indefinite service life with proper design and
maintenance
Typical Deterioration Conditions
Cracking
Spalling
Delamination
Displacement
Efflorescence
Mortar condition
Prior remedial treatments
Envelope Exterior - Masonry

17. Envelope Exterior - Masonry

18. Condition of Façade Materials: Precast Panels
Indefinite service life with proper design and
maintenance
Typical Deterioration Conditions
• Cracking
• Spalling
• Prior remedial treatments
Envelope Exterior - Concrete

19. Condition of Façade Materials: Glazing Systems
10-20 year lifespan (sealants and gaskets )
50+ year lifespan -CW structure and single pane glazing
Traditional Windows
• Flanged
• Punch
Systems
• Curtainwall / Unitized
• Stick/Storefront
Sealants/Gaskets
• Polyurethane
• Silicone
• Compressed gaskets
• Zipper gasket
• Structural silicone
Envelope Exterior – Curtainwall & Windows

20. Insulated panels
Metal building type
Aluminum composite panels
Copper or Stainless Flashing
20-40 year service life with proper design and
maintenance
Typical Deterioration Conditions
• Oil-canning
• Corrosion
Envelope Exterior – Metal

21. Step Two - Present Options & Constructability Review
• Design Alternatives
• Impact of Codes and Standards
• Hidden Conditions
• Constructability
• Budget

22. Physical/Structural Characteristics of the
Building Envelope
Deficiencies in one or more of these areas
can lead the decision matrix for
recladding:
• Condition of Lateral Support Systems
• Condition of Substrate/Weatherbarrier
• Condition of Structure (At perimeter)
Hidden Conditions

23. • Arms-length investigation
• In-situ testing
• Non-destructive Evaluation
Investigative Techniques

24. • Condition of Substrate/Weatherbarrier
• Does system permit remedial repair of
lateral systems?
• Does a weather barrier exist?
• Water
• Air
• Vapor
• Insulation
• What is condition of existing materials?
• Antiquated systems
• Asbestos Containing Materials
• Water Damage
Substrate Analysis

25. Systems are typically concealed
Failure represents significant risk to public safety
Typical warning signs
• Outward displacement of masonry
• Spalling
• Localized failure
Current wind
load requirements
VS
Building Code in effect
at time of construction
Condition of Lateral Support Systems

26. Condition of Structure (At perimeter)
• Façade elements may restrict access to
superstructure
Condition of Structural Frame & Foundation

27. Thermal performance of existing wall
Wufi Model to evaluate existing
Wufi Model to evaluate proposed renovation
Affect of hot-humid climate
Affect HVAC assumptions/systems and operation - Existing and Future
Review of Water Vapor Permeance

28. Air and Water permeance of existing wall
Air/Water vapor barrier location and integrity
Vapor drive - new 2013 materials vs Historic or late 20th
century alternates
Tar paper
Tyvek
Peel & stick
Mass wall
Intrusion from leaks –
any opening in envelope
Review of Water Vapor Permeance

29. Tools for review of Insulation & Vapor Barrier

30. Sample WUFI Output
Air Temperature
Dew PointRelative Humidity
Water Content
Exterior Interior
BRICK
CAVITY
AIR BARRIER
& EXT. GYP
INSULATION
INT. GYP. &
VINYL
WALLPAPER
3 Year
Cycle
Shaded Area =
3 Year Cycle
Tools for review of Water Vapor Dewpoint

31. • THERM's heat-transfer analysis allows you to evaluate a
system energy efficiency and local temperature
patterns, which may relate directly to problems with
condensation, moisture damage, and structural integrity.
Tools for review of Thermal Performance

32. Step Three - Cost Benefit Analysis
Building Life-Cycle Cost (BLCC) Program—Economic analysis tool developed by the
National Institute of Standards and Technology for the U.S. Department of Energy
Federal Energy Management Program (FEMP).
http://www1.eere.energy.gov/femp/information/download_blcc.html#blcc
http://www.wbdg.org/tools/athena_eie.php
LCCA can be performed at various levels of complexity. Its scope might vary
from a "back-of-the-envelope" study to a detailed analysis with thoroughly
researched input data, supplementary measures of economic
evaluation, complex uncertainty assessment, and extensive documentation.
The extensiveness of the effort should be tailored to the needs of the project.

33. Owner’s long term plans : calculate the life cycle implications of recladding vs. cladding
repair.
Government - Lifetime
Developer - 100% Lease and Sell
Owner/Operator - Lifetime with Exit strategy
High Maintenance cost – deferred maintenance problem
Life Cycle Cost Analysis

34. At what point does the cost of
remediation approach the cost of
recladding?
Repair vs Reclad
Low cost
Repair
High Cost
Removal
Repair Scope Extents of façade material removal
Improve Performance of façade systems Typically local
Repair of Vertical Support Systems Typically local (10%)
Repair of Structure Typically local (20%)
Repair of Façade materials Varies greatly - Local to Global
Repair of Lateral Support Systems
Minimal with appropriate substrate,
Global with poor substrate
Repair of Substrate Typically global
Extents of façade removal required for various repairs

35. Park Towers - 2000
YEAR BUILT: 1972
ENVELOPE REVIEW ISSUE: New Owner
PROJECT START DATE: 1998
COST: $27M Core & Shell + Garage
DESIGN SUMMARY – Vacant 13 years;
purchase price allowed consideration of re-
branding for new Class-A image. 24” floor
extension was added to perimeter for NRA of
24,000 SF
Case Study – Park Towers RECLAD

38. Restore for Historic Significance and PerformanceCase Study – U of H Roy G Cullen RESTORE
YEAR BUILT: 1938
ENVELOPE REVIEW ISSUE: Campus Master Plan, Water
Intrusion of Historic First Building on U of H Campus
PROJECT START DATE: Not Started
PROJECT COST: Est. $3.2 M
DESIGN SUMMARY: Detailed review of documents and
Broroscope investigation revealed that water intrusion was
impacting limestone anchors. Previous re-windowing was not
draining correctly. Limestone panels spalling.

41. Case Study – Sylvan Beach Pavilion RECLAD + RESTORE
YEAR BUILT: 1956 with 1962 & 1980 additions
ENVELOPE REVIEW ISSUE: Hurricane Ike Damage to
Curtainwall – Building abandoned since damage
PROJECT START DATE: 2012
PROJECT COST: $3.2 Million
DESIGN SUMMARY: Historic Restoration of 1950’s Mod Building
for Harris County.

44. YEAR BUILT: 1973
ENVELOPE REVIEW ISSUE: Campus precast buildings had
some repairs and exposed rebar and spalls, but iconic imagery in
a build to suit campus.
PROJECT START DATE: 2009
PROJECT COST: $300 Million
DESIGN SUMMARY: Restoration of Campus Lab Building with
interior and glass element update for new office use
Case Study – Shell Technology Center RESTORE

48. Pros
• New head height at window openings (9’-0”) allows more daylight and use of underfloor air on both floors.
• Replacing glass w/ high performance low-e glass allows more visible light, less solar heat gain
• Improved waterproofing at windows and overall exterior with new installation
• New window mullion spacing will be closer to 5’-0” OC
• Replacement of monitor allows upgrade of 30 year old pipe infrastructure. It allows phased replacement
during construction by having pipes at base roof level installed prior to demo. Future maintenance of piping
at roof level is safer. Re-using structural slab (previous monitor floor) below pipe rack improves
waterproofing below pipes.
• Replacement of monitor improves campus appearance by lowering overall height of secondary roof
structure.
• New skylight at center allows double loaded office with perimeter circulation on glass and along skylight
• Additional demo will require construction waste recycling
• Construction sequence will expose interior to weather; requires full building shut down to optimize
contractor’s work time
Cons

50. If 30% - 50% of exterior cladding must be removed for
remediation, replacement may be a more cost effective
alternate, depending on cost of cladding materials.
Integrity of Façade Assembly
Other factors – what is the business decision?!
• Will new façade lead to increase in rent?
• Can it lower energy usage?
• Project staging - is building occupied?
Re-skin vs Rehabilitate Existing

51. Typically Reactive
Implementation
Mandates Periodic
Inspections
Future – Façade Ordinances

52. Questions?
This concludes The American Institute of Architects Continuing Education Systems
Course

54. Sustainable Design
The BIM model allows for early staged energy
calculations using DOE-2 compatible energy
modeling software. This helps with glazing
selection and adds valuable cost/payback
calculations for the owner.
BIM @ Kirksey

55. • EVALUATION Structural
Air / Water /Heat infiltration
Market position Site and
Context
• COST Project cost
life cycle cost improved
energy performance.
• APPEARANCE Historic
importance of the façade Market
position Site and Context
•