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Junction ψ-values and f-values (walls with cavities fully filled with Xtratherm CavityTherm)

Thermal bridging ψ-values and f-values for walls fully filled with Xtratherm CavityTherm insulation.

SAP 2012 Table K1 ref: E2
Junction Detail: Other lintels (including other steel lintels)
SAP2012 Approved ψ-value (W/mK): 0.30
SAP2012 Default ψ-value (W/mK): 1.00
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.023 to 0.058
Lightweight: 0.022 to 0.058
Dense: 0.022 to 0.058
CBA detail ref: CT001

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CBA detail ref: CT002

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SAP 2012 Table K1 ref: E3
Junction Detail: Sill
SAP2012 Approved ψ-value (W/mK): 0.04
SAP2012 Default ψ-value (W/mK): 0.08
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.032 to 0.037
Lightweight: 0.032 to 0.036
Dense: 0.032 to 0.036
CBA detail ref: E3 CBA CT 003

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SAP 2012 Table K1 ref: E4
Junction Detail: Jamb
SAP2012 Approved ψ-value (W/mK): 0.05
SAP2012 Default ψ-value (W/mK): 0.10
Calculated CBA Full-fill ψ-value (W/mK):  Ultra-lightweight: 0.000 to 0.023
Lightweight: 0.000 to 0.023
Dense: 0.000 to 0.023

CBA detail ref: E4 CBA CT 004

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CBA detail ref: E4 CBA CT 005

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SAP 2012 Table K1 ref: E5
Junction Detail: Ground Floor (Normal)
SAP2012 Approved ψ-value (W/mK): 0.16
SAP2012 Default ψ-value (W/mK): 0.32
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.035 to 0.051
Lightweight: 0.063 to 0.077
Dense: 0.154 to 0.166
CBA detail ref: E5 CBA CT 020 (Beam and Block)

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SAP 2012 Table K1 ref: E7
Junction Detail: Intermediate floor between dwellings*
SAP2012 Approved ψ-value (W/mK): 0.07
SAP2012 Default ψ-value (W/mK): 0.14
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.034 to 0.049
Lightweight: 0.034 to 0.050
Dense: 0.035 to 0.052
CBA detail ref: E7 CBA CT 007

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SAP 2012 Table K1 ref: E15
Junction Detail: Flat roof with parapet
SAP2012 Default ψ-value (W/mK): 0.56
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.084 to 0.101
Lightweight: 0.111 to 0.127
Dense: 0.219 to 0.224
CBA detail ref: E15 CBA CT 015

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SAP 2012 Table K1 ref: E16
Junction Detail: Corner Normal
SAP2012 Approved ψ-values (W/mK): 0.09
SAP2012 Default
ψ-value (W/mK): 0.18
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.036 to 0.044
Lightweight: 0.038 to 0.048
Dense: 0.041 to 0.052
CBA detail ref: E16 CBA CT 016

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SAP 2012 Table K1 ref: E17
Junction Detail: Corner (inverted – internal wall area greater than external area)
SAP2012 Approved ψ-values (W/mK): -0.09
SAP2012 Default
ψ-value (W/mK): 0.00
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: -0.072 to -0.059
Lightweight: -0.074 to -0.061
Dense: -0.076 to -0.062
CBA detail ref: E17 CBA CT 017

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SAP 2012 Table K1 ref: E17
Junction Detail: Party (separating) wall between dwellings*
SAP2012 Approved ψ-values (W/mK): 0.03
SAP2012 Default
ψ-value (W/mK): 0.06
Calculated CBA Full-fill ψ-value (W/mK): Ultra-lightweight: 0.034 to 0.046
Lightweight: 0.035 to 0.047
Dense: 0.037 to 0.048
CBA detail ref: E18 CBA CT 018

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SAP 2012 Table K1 ref: E19
Junction Detail: Ground Floor (inverted)
SAP2012 Default ψ-value (W/mK): 0.07[/toggle][toggle title=”E20 Exposed Floor (normal)” open=”no”]
SAP 2012 Table K1 ref: E20
Junction Detail: 
Exposed Floor (normal)
SAP2012 Default ψ-value (W/mK): 0.32[/toggle][toggle title=”E21 Exposed Floor (inverted)” open=”no”]
SAP 2012 Table K1 ref: E21
Junction Detail: Exposed Floor (inverted)
SAP2012 Default ψ-value (W/mK): 0.32

SAP 2012 Table K1 ref: P8
Junction Detail: Exposed floor (exposed)*
SAP2012 Default ψ-value (W/mK): 0.24[/toggle][toggle title=”P4 Roof (insulation at ceiling level)*” open=”no”]
SAP 2012 Table K1 ref: P4
Junction Detail: Roof (insulation at ceiling level)*
SAP2012 Default ψ-value (W/mK): 0.24[/toggle][toggle title=”P5 Roof (insulation at rafter level)*” open=”no”]
SAP 2012 Table K1 ref: P5
Junction Detail: Roof (insulation at rafter level)*
SAP2012 Default ψ-value (W/mK): 0.04