Short Rapid-Fire Presentation from Seattle AIA Building Envelope Forum on Super Insulated Walls and Roofs

1. Stuff It or Wrap It? Considerations for
Super Insulated Walls & Roofs
SEATTLE AIA BUILDING ENVELOPE FORUM – DECEMBER 9, 2014
GRAHAM FINCH, MASC, P.ENG – PRINCIPAL, RDH BUILDING SCIENCES

2. CAUTION: Insulation!
Caution! Lots of
Insulation &
Innovation

3. Industry Drivers & Trends towards Super Insulation
 Trend towards more efficiently insulated
building enclosures due to higher energy
code targets and uptake of passive design
strategies
 At a point where traditional assemblies are
being replaced with new ones
 Seeing more new building materials,
enclosure assemblies and construction
techniques
 Greater attention paid to reducing thermal
bridging & use of effective R-values instead
of nominal insulation R-values
 Optimization of cladding attachments for
both structural and thermal performance
 Thicker amounts of insulation – particularly
in low-slope roofs

4. Key Building Enclosure Considerations
 “Super-Insulated” building enclosures require
careful design and detailing to ensure
durability
 Art of balancing various materials, costs, and
detailing considerations
 Shift insulation to the exterior the structure
to improve performance and durability
 Minimize thermal bridging by optimizing
structural connections and other components
 Well insulated buildings require balancing
thermal performance of all components &
airtightness
 No point super-insulating walls or roofs if
you have large thermal bridges - address the
weakest links first

5. From Code Minimum to Super Insulation
 In Pacific Northwest (Climate Zones 3 – 6)
minimum energy code R-value targets are in
range of:
 R-15 to R-20 effective for walls
 R-20 to R-50 effective for roofs
 R-2 to R-4 for windows
 Green or more energy efficient building
programs including Passive House, R-value
targets in range of:
 R-25 to R-50+ effective for walls
 R-40 to R-80+ effective for roofs
 R-6+ for windows
 Other drivers – air-tight, thermal comfort,
passive design, mold-free

6. Where to Add the Insulation?
Stuff It?
Wrap It?

7. Getting to Super Insulation Levels in Walls
Baseline
2x6 w/ R-22
batts = R-16
effective
Exterior Insulation: R-20 to R-40+ effective
• Constraints: cladding attachment, wall
thickness
• Good for wood/steel/concrete
Deep/Double Stud:
R-20 to R-40+
effective
• Constraints wall
thickness
• Good for wood,
wasted for steel
Split Insulation:
R-20 to R-40+ effective
• Constraints: cladding
attachment
• Good for wood, palatable
for steel

8. 10
15
20
25
30
35
40
45
5 6 7 8 9 10 11 12 13 14 15
EffectiveR-valueofWall
Total Wall Thickness (Excluding Cladding) [inches]
Effective Wall R-value versus Wall Thickness
Split Insulated
(2x6) & R-4/inch
EI
Split Insulated
(2x6) & R-4/inch
EI (w/ Screws)
Split Insulated
(2x4) & R-4/inch
EI
Split Insulated
(2x4) & R-4/inch
EI (w/Screws)
Double Stud
(2x4) w/ R-
3.4/inch Ins.
TJI Stud w/ R-
3.4/inch Ins.
Insulation Approach & Wood-frame Wall Thickness
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
5 6 7 8 9 10 11 12 13 14 15
PercentThermalDegradationofInstalledInsulation
Total Wall Thickness (Excluding Cladding) [inches]
Thermal Degradation of Insulation
versus Wall Thickness

9. Cladding Attachment & Exterior Insulation
 Exterior insulation is only as good as the
cladding attachment strategy
 How to achieve true continuous insulation
(ci) performance?
 What attachment systems work best?
 What types of insulation?

10. Many Alternate Attachment Options & Counting

11. Continuous Metal Girts – Not Super Insulated

12. Metal Clip & Rail – Getting Better

13. Thermally Improved Clip & Rail Systems

14. Screws through Exterior Insulation

15. Cladding Attachment Matters – Effective R-values
20
30
40
50
60
70
80
16.8 33.6 50.4
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
NO PENETRATIONS
Nominal R-Value of Exterior Insulation (ft2·°F·hr/BTU)
4” – R-16.8 8” – R-33.6 12” – R-50.4
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" OC
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x 48"
Intermittent Galvanized Z-Girt - 16"x 24"
Isolated Galvanized Clip - 16" x 48"
20
30
40
50
60
70
1
6
.
3
3
.
5
0
.
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" OC
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x 48"
Intermittent Galvanized Z-Girt - 16"x 24"
Isolated Galvanized Clip - 16" x 48"
Isolated Galvanized Clip - 16" x 24"
Intermittent SS Z-Girt - 16" 48"
Intermittent SS Z-Girt - 16" x 24"
Fiberglass Clip - 16" x 48"
Fiberglass Clip - 16" x 24"
Galvanized Screws - 16" x 16"
20
30
40
50
60
70
1
6
.
8
3
3
.
6
5
0
.
4
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" OC
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x
Intermittent Galvanized Z-Girt - 16"x
Isolated Galvanized Clip - 16" x 48"
Isolated Galvanized Clip - 16" x 24"
Intermittent SS Z-Girt - 16" 48"
Intermittent SS Z-Girt - 16" x 24"
Fiberglass Clip - 16" x 48"
Fiberglass Clip - 16" x 24"
Galvanized Screws - 16" x 16"
Galvanized Screws - 16" x 12"
SS Screws - 16" x 16"
SS Screws - 16" x 12"
Effective R-Value of 2x6 Wall (R-20 batt) + Exterior Insulation as Indicated
20
30
40
50
60
70
80
16.8 33.6 50.4
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
NO PENETRATIONS20
30
40
50
60
70
80
16.8
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6 50.4
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/B
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Va
NO PENETRATIONS20
30
40
50
60
70
80
16.8
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Valu
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6 50.4
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6 50.4
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
NominalR-ValueofExterior Insulation(ft2· F·hr
NO PENETRATIONS
NO PENETRATIONS
20
30
40
50
60
70
80
16.8 33.6
EffectiveR-ValueofWholeWallAssembly
(ft2·F·hr/BTU)
NominalR-ValueofExteriorInsulation(ft2· F·hr/BTU)
NO PENETRATIONS
NO PENETRATIONS

16. 0%
20%
40%
60%
80%
16.8 33.6 50.4
PercentThermalDegredationofExteriorInsulation
Nominal R-Value of Exterior Insulation (ft2· F·hr/BTU)
Towards Super Insulation with Exterior Insulation
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" OC
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x 48"
Intermittent Galvanized Z-Girt - 16"x 24"
Isolated Galvanized Clip - 16" x 48"
20
30
40
50
60
70
1
6
.
3
3
.
5
0
.
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" OC
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x 48"
Intermittent Galvanized Z-Girt - 16"x 24"
Isolated Galvanized Clip - 16" x 48"
Isolated Galvanized Clip - 16" x 24"
Intermittent SS Z-Girt - 16" 48"
Intermittent SS Z-Girt - 16" x 24"
Fiberglass Clip - 16" x 48"
Fiberglass Clip - 16" x 24"
Galvanized Screws - 16" x 16"
20
30
40
50
60
70
1
6
.
8
3
3
.
6
5
0
.
4
Continuous Vertical Z-Girt - 16" OC
Continuous Horizontal Z-Girt - 24" O
Aluminium T-Clip - 16" x 48"
Aluminium T-Clip - 16" x 24"
Intermittent Galvanized Z-Girt - 16" x
Intermittent Galvanized Z-Girt - 16"x
Isolated Galvanized Clip - 16" x 48"
Isolated Galvanized Clip - 16" x 24"
Intermittent SS Z-Girt - 16" 48"
Intermittent SS Z-Girt - 16" x 24"
Fiberglass Clip - 16" x 48"
Fiberglass Clip - 16" x 24"
Galvanized Screws - 16" x 16"
Galvanized Screws - 16" x 12"
SS Screws - 16" x 16"
SS Screws - 16" x 12"
Percent Thermal Degradation of Exterior Insulation
Nominal R-Value of Exterior Insulation (ft2·°F·hr/BTU)
4” – R-16.8 8” – R-33.6 12” – R-50.4

17. Getting to Super Insulation Levels in Low-Slope Roofs
Baseline (Vented
Roof) ~R-30
Exterior Insulated
(Conventional or
PMR Roof)
• Best durability but
most expensive
• Some challenges with
more layers of
insulation & detailing
• Simple design
Deeper Joist/Truss –
(Vented or Unvented
Roofs)
• Least durable but
least expensive
• Simple design
• Standard details with
deeper structure
Split Insulated
(Unvented Roof)
• Decent durability
• Moderate cost
• More complex
design

18. Some Considerations for Super Insulated Roofs

19. Some Considerations for Super Insulated Roofs
4” stone wool
+
4” polyiso
+
2-8” EPS
=
R-50+

20.  rdh.com
Discussion
GRAHAM FINCH – GFINCH@RDH.COM – 604.873.1181