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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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