U-VALUE CALCULATOR

VERSION 1.5.4

Step 3. Construction build-up for calculations

1F felt with insulation between rafters & TLX Silver under rafters

Roof tiles
25mm Ventilated airspace
Type 1F felt
50mm Ventilated airspace
Unventilated airspace between rafters (minimum 20mm)
Cross battens
Cross battens
Unventilated airspace between battens (minimum 20mm)

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