This document provides an overview of light weight panelized construction using rainscreen ventilated wall systems (RVRS) in multiple building projects. It begins with an introduction to key partners and speaker Blair Davies. The bulk of the document consists of 5 case studies of specific projects using different panel materials like ceramic, fibre cement, and recladding examples. It discusses attributes of RVRS, definitions, standards, and debates around pressure equalization. It raises unanswered questions and reviews relevant sections of the Ontario Building Code. The goal is to demonstrate how RVRS has been successfully used across different project types and materials at both new construction and renovation scales.

1. Case Studies of RVRS design; Use of
Light Weight Panelized Construction in
Multiple Projects
OBEC
March 2016
Blair Davies, P.Eng
VP GM Engineered Assemblies
- March 9, 2016page 1

2. Engineered Assemblies
“Unite the House of Design with The Field of Construction”
– Thermally Broken RVRS Facades
– Daylighting
– High performance Metal Roofs
Partners
» Etex - Imetco
» Composites Gurea - SRP Canada
» Formica - AWF
» Gentas - CPI Daylighting
>1000 projects; no warranty claims, no non payment for non performance
Sister company Praxy installation Ontario
- March 9, 2016page 2

3. Speaker
Blair Davies, P.Eng
– BaSc University of Waterloo – Civil Engineering
– MBA Schulich School of Business
– Building envelope business since 2008
– Buildings across Canada
- March 9, 2016page 3

4. Agenda
• Introduction – does all this matter?
• What matters
• Definition and history
– DIN 18516
– British Standards
• Pressure Equalization – the debate
• Case Study #1
– Parliament St Data Centre – ceramic
• Case Study #2
– McLean Park Towers – fibre cement
• Case Study #3
– 88 Sheppard, Minto – fibre cement
• Case Study #4
– 2 Virtue Street – fibre cement recladding
• Case Study # 5
– Addington Residence – ceramic recladding
• Unanswered questions
• Conclusion
• Ontario Building Code
• Discussion
- March 9, 2016page 4

5. Is all this necessary?
- March 9, 2016page 5

6. What matters
• Ventilation
• Drainage
• Thermal Bridging
• Secure
• Impact
• Weight
• Durable
• Constructible
• Climate and weather
• Acoustics
- March 9, 2016page 6

7. Light weight matter?
• Fibre cement 15 kg/m2
• Ceramic 35 – 50 kg/m2
• Metal 4.5-7.3 kg/m2
• Steel stud wall; insulation;
thermally broken substructure
20kg/m2 (GUESS)
• Brick 174 kg/m2
• Precast(300mm) 718 kg/m2
• EIFS (100mm) 8 kg/m2
• Curtain wall 49 kg/m2
- March 9, 2016page 7

8. Define RVRS
• Cladding stands off the moisture resistant surface
to create a drainage plane and ventilation cavity.
• Vertical cavity for stack effect and capillary break.
• The wall open top and bottom to allow ventilation,
• Intermediate gaps open or closed; aesthetic decision.
• Insulated or non-insulated.
- March 9, 2016page 8
Source: Wikipedia

9. - March 9, 2016page 9
• Framing – stud, concrete,
brick, etc
• Sheathing, AVB
• Insulation
• Weather barrier
• Cavity
• Panels
• Thermally
Broken
substructure

10. - March 9, 2016page 10
Detail in
practice

11. 11
Key Attributes of RVRS Facades?
• Remove water and vapour in active, natural manner from assembly
• Exterior takes abuse of the weather - full heat, the sun, the wind…
• Ventilation helps the building AND the façade product
• Accommodates any amount of insulation
• Insulation is always drying - better effective R
• Simpler, more easily built and inspected - no caulking
• Lighter thinner systems than concrete and brick
• Unlimited choice in panel selection.
• Better energy efficiency than most curtain wall
• Less expensive than many other systems

12. History and Standards
• Ventilated façade in Europe
– DIN 18516 – German Construction Standard
• Specifies all key attributes
• Spacing behind panel minimum 20mm
– CWCT H92
– NBS British Construction Standard
• Canadian Construction Technology Update
– 1963 NRC
– 1999 CTU
– Cladding leakage area to Ventilation area suggested 10:1
• USA NIBS
- March 9, 2016page 12

13. DIN 18516
• Covers
– Scope and field of application
– Concepts
– Requirements
– Design loads, thermal effects and structural movements
– Structural analysis
– Protection of materials
– Testing of connectors, fixing and ties
– Documentation
– Inspection
- March 9, 2016page 13

14. NBS Section H92
• Vertical building envelope; Outer skin
• Airtight insulated backing wall, separate by ventilated cavity
• Key distinction is that curtain walling is usually the whole
envelope, while rainscreen cladding is the outer protective
layer of the envelope.
- March 9, 2016page 14

15. Business Opportunity
• Materials developed to leverage RVRS mostly from Europe
– High density fibre cement
– Glass reinforced concrete
– Phenolic
– Ceramic
– Porcelain
– Metals
– Stone laminates
– Wood panels
– Hybrids
• Subsystems
• Design
• Labour
- March 9, 2016page 15

16. RVRS suitable for all building types
HouseCondo HotelUniversity SchoolHospital

17. Alcoa building pittsburgh
1950 1st modern use

18. Walter Gropius,
gropiusstadt, Berlin,
b1960-1975
Eternit panels in high
rise ventilated facade
application

19. Pressure Equalization • Ideal
• Ambiguous
• Planning ≠ Actual
• Structural considerations
• Not part of European standards
- March 9, 2016page 19
Sources include: National Building Service UK 1-Jan-2010 “Rainscreen cladding; letting air in to keep rain out”

20. P.E. - compartmentalization
• Horizontal closures so air can get in, but can’t get out
• Seeing specifications with compartmentalization
• Some study that at façade corners and parapets this helps PE.*
• Europeans products do not recognize this practice
- March 9, 2016page 20
Source: MCA Whitepaper 11/2014 v2
NRC CTU no 17 1998
Graphic by Nichiha

21. Rain Screen Membrane
• Water resistant, water vapour permeable membrane
• Secondary drainage plane
• Aesthetic black reveal with long term UV resistance
for open joint systems
• Can be the deemed air barrier if sealed
• Installed directly behind cladding
- March 9, 2016page 21

22. Weather Membrane
§ For Closed Joint Systems (with no long term UV)
• High WVT 150 perms
• 120 g/m2
• Drainage Plane
• CCMC listed
• Air Barrier
Courtesy

23. Drying Rate
MVTR (perms)Comparison
0
20
40
60
80
100
120
140
160
Prod 1 Prod 2 Prod 3 Prod 4
Perms
Perms
Courtesy

25. Weather membrane UV
§ For Open Joint Wall Systems (long term UV)
• Long Term UV Resistance
l DIN EN 13859 (5,000 hours exposure <5% loss)
• Drainage Plane
• Air Barrier
courtesy

26. 26

27. 27
Installation
Ø Attachment
l Over insulation, behind cladding
l Clips or system support, screws with plates
Ø Overlapping
l Shingle style with 6 inch overlap
Ø Seams
l Tape vertical seams and details
l Tape all seams in Air Barrier installations

28. • Robust
• Breathable
• Water Resistant
• UV Resistant
Why Weather Membrane?

29. Panels
page 29
Zinc
ACP
FRC &
GFRC
Phenolic
PorcelainCeramic
ACP
Stone
veneer
Unlimited choice

30. All conditions have been done
- March 9, 2016page 30

31. Case Study 1
Data Centre
• Parliament St Data Centre
• Cladding, cavity, WB, Insulation, Thermally broken substructure,
AVB, framing.
• Effective R Value Goal 21
• Extruded Ceramic (35kg/m2) + Ceramic Baguettes
• Cavity dimension = 40mm vertical + 63mm.
• Insulation type = Roxul Cavity Rock 4” (100mm)
• WB type = SRP Airoutshield
• AVB type = Soprema
• Special conditions: designed for disaster conditions, so extreme
slab deflections expected
• Why: “Relate local masonry in modern way to reflect use of
building” WZMH
• Architect WZMH, GC Urbacon, Installer Flynn Canada
- March 9, 2016page 31

32. - March 9, 2016page 32

33. - March 9, 2016page 33

34. - March 9, 2016page 34

35. Case Study 2 - McLean Park
Towers – Tower Renewal
• Social housing, Vancouver
• High Density Fibre Cement, vertical girts, WB, thermally
broken substructure, AVB, Concrete
• HDFC 14.9 kg/m2 faced fastened with colour matched rivets
• 25mm cavity with vertical galvanized steel girts
• Roxul Cavity Rock 4” (100mm)
• Thermally broken facade
• Vaproshield WB
• Soprema AVB
• Special conditions:
• JRS Engineering; Installer Marine Cladding
- March 9, 2016page 35

36. - March 9, 2016page 36

37. Case Study 3
88 Sheppard E, Minto
• HDFC, Vertical girts, cavity, WB, insulation and girts, AVB,
Framing or Concrete
• Effective R value not a goal
• HDFC 14.9 kg/m2 adhered with Dynamic Bond Adhesive
• Cavity dimension 25mm
• Roxul semi-rigid rockboard 40 2” and 3”
• Roxul curtain rock 5”SRP AirOutShield UV
• AVB type TBD
• Rafael + Bigauskas Architects; GC and Owner Minto; Installer Praxy Cladding
- March 9, 2016page 37

38. - March 9, 2016page 38
Details – need direction

39. - March 9, 2016page 39

40. - March 9, 2016page 40
AVB
WB

41. Case Study 4
• 2 Virtue Street
• HDFC, girts, cavity, breather
membrane over brick
• Un-insulated
• HDFC 14.9 kg/m2
• Cavity dimension 25mm
• SRP AOS UV
• AVB poly inside studs
- March 9, 2016page 41

42. - March 9, 2016page 42
Renovation adds new vigour to a sagging
Toronto home Aug 2013

43. Case Study 5
Addington Residence U
Guelph
• Ceramic panels, system rails, weather
membrane, horizontal girts, sprayfoam insulation
on top of brick façade
• Ceramic 35 kg/m2
• Cavity dimension 20mm
• Spray foam 4” (100mm)
• SRP AOS non UV WB
• Blueskin SA behind girts, Spray foam is AVB
• Unique: Brick fastened back to block, and cavity
filled. Insulated rainscreen fastened to brick
façade
- March 9, 2016page 43
Larkin Architects; GC Harbridge and Cross; Installer AMNA

44. - March 9, 2016page 44

45. What would it take to make a real case
study – anyone?
• Instrumentation
• Long term study of RH in insulation
• Measurement during weather incident
- March 9, 2016page 45

46. Construction Best Practices
• 5 things need to be done right to have RVRS success with
panelized products eg high density fibre cement.
1. Ventilation top and bottom.
2. Vertical substructure for ventilation.
3. Panels allowed to move for thermal and for building
movement, typically with fixed and floating points.
4. Substructure spacing set by live and dead loads.
5. Reasonably true wall or adjustable substructure
- March 9, 2016page 46

47. Unanswered questions
• What happens to wet insulation over long term?
• Why isn’t metal panel / ACP installed as RVRS?
• Why does OBC not cover topic completely?
• Why are product choices in Canada limited?
- March 9, 2016page 47

48. Conclusion
• RVRS Façade a significant design choice for aesthetic and
envelope performance reasons
• Engineered extensively, mostly in Europe
• Business opportunity for Canadians
• A few things need to be done right, but reasonable for most
cladding trade companies to learn
• Thankyou.
- March 9, 2016page 48

49. OBC
Review
• Part 4 Structural
– All systems can be designed for all Canadian loads by changing
spacing, gauge and material of substructure.
– Seismic testing available for heavier facades eg ceramic. No
call yet for testing of phenolics, fibre cement, metal panel
– Panels themselves designed to pass live loads back to
substructure, not provide any structural role to the building.
• Part 5
– 5.1.4.2 Resistance to Deterioration
– CSA S478 Durability of Buildings
– 5.2.2.1 Determination of Structural loads – comply
– 5.3.1 Thermal resistance – not the panels, just the insulation
layer. Expectation is cavity has higher or lower temp than
outside, improving energy usage – needs proving.
• Important to design due point in right place between AVB and
Weather membrane
• Penetration detailing essential – thermal bridging and air transfer
to be eliminated
– 5.4.1 Air Barrier – at least two layers of protection, insulation
may offer another or replace a barrier.
- March 9, 2016page 49

50. OBC
• 5.4.1.2 Air Barriers CAN/ULCS741
• 5.5.1.1 (1) assemblies shall be such that they control vapour
diffusion or permit venting to the exterior so as to minimize
accumulation of condensation in the building component or
assembly.
• 5.6.1 Protection from Precipitation
– Except as provided in Sentence (2), where a building
component or assembly is exposed to precipitation, the
component or assembly shall,
• (a) minimize ingress of precipitation into the component or
assembly, and
• (b) prevent ingress of precipitation into interior space.
– (2) Protection from ingress of precipitation is not required
where it can be shown that such ingress will not adversely
affect any of ….
• 5.6.2 Sealing and drainage – reads like sealing is good. May
have misguided intentions.
- March 9, 2016page 50

51. OBC • Part 9 is different
– 9.20.13. Control of Rain Water Penetration
– 9.25.3. Air Barrier Systems
– 9.25.4. Vapour Barriers
– 9.25.5. Properties and Position of Materials in Building
Envelope
– 9.27. Cladding TBD
- March 9, 2016page 51

52. Rear Ventilated Rain Screen
(Moisture Management)
Drainage and ventilation
Some water gets
in, and then
drains out.
Condensation
and water vapour
vented to
exterior.

53. Alternatively – Single Skin Construction. Water always
gets in causing deterioration
Crack

54. Drained cavity Rainscreen eg Masonry
• Masonry uses Rainscreen term – different
than RVRS
• Drainage of water that penetrates the
brick is allowed to drain out
• Limited to no ventilation; closed top and
bottom of wall.
• Less active plenum; reducing benefit of
ventilation
• Constructability issues with ensuring
drainage is working
• Heavier, more steps to build
- March 9, 2016page 54

55. RVRS (Insulation)
NATURAL INSULATION – 0.5 R Value from RVRS
Energy Efficiency
Consumption of
AC/Heating
Acoustic Insulation

56. RVRS
(Temperature Regulation)
When the outside temperature is HOT, the ventilated rain
screen cladding has a cooling effect on the building
• Most of the sun’s rays are reflected
• Ventilating effect of the air gap

57. RVRS
(Temperature Regulation)
When the temperature is COLD outside the same process occurs:
• Most of the cold air is
reflected by the exterior
architectural panel
• The remaining cool air will
partially dissipate by the ventilating
effect of the air gap between the
architectural panel and the structural wall
• Insulation is protected, so will remain effective