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Roof U-Value Calculations

Roof Type 1 - Description: 

12mm Roof Tiles, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 12.5mm Plasterboard

Condensation Calculation

SIP Thickness

​

219mm

​

194mm

​

169mm

​

144mm

​

​

Total Roof Thickness

​

319mm

​

294mm

​

269mm

​

244mm

​

​

U-Value

​

0.13W/m²K

​

0.15W/m²K

​

0.17W/m²K

​

0.20W/m²K

​

​

U-Value

Calculation

Roof Type 2 - Description: 

12mm Roof Tiles, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 50mm Gyproc Thermaline Super

U-Value Calculation

SIP Thickness

​

219mm

​

194mm

​

169mm

​

144mm

​

​

Total Roof Thickness

​

356mm

​

331mm

​

306mm

​

281mm

​

​

U-Value

​

0.10W/m²K

​

0.11W/m²K

​

0.12W/m²K

​

0.14W/m²K

​

​

Condensation Calculation

Flat Green Roof - Description: 

Green roof covering, 19mm ply, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 12.5mm Plasterboard

SIP Thickness

​

219mm

​

194mm

​

Total Roof Thickness

​

348mm

​

323mm

U-Value

​

0.14W/m²K

​

0.16W/m²K

​

Condensation

Calculation

U-Value

Calculation

Flat Green Roof - Description: 

Green roof covering, 19mm ply, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 50mm Gyproc Thermaline Super

SIP Thickness

​

219mm

​

194mm

​

Total Roof Thickness

​

385mm

​

360mm

U-Value

​

0.11W/m²K

​

0.11W/m²K

​

U-Value Calculation

Condensation Calculation

Flat EPDM Roof - Description: 

EPDM Rubber roof covering, 19mm ply, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 12.5mm Plasterboard

SIP Thickness

​

219mm

​

194mm

​

Total Roof Thickness

​

324mm

​

299mm

U-Value

​

0.14W/m²K

​

0.16W/m²K

​

Condensation Calculation

U-Value Calculation

Flat EPDM Roof - Description: 

EPDM Rubber roof covering, 19mm ply, 50mm ventilated air layer, Protect VP400 Plus LR Membrane, SIP at specified thickness, Protect VC Foil Ultra Insulating A VCL, 25mm Service void, 50mm Gyproc Thermaline Super

SIP Thickness

​

219mm

​

194mm

​

Total Roof Thickness

​

361mm

​

336mm

U-Value

​

0.11W/m²K

​

0.11W/m²K

​

U-Value Calculation

Condensation Calculation

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