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Inverted Roof Insulation

ProTherm XPS Layer


ProTherm XPS Layer is used to compliment the thermal performance of ProTherm Quantum VIP Panels, and as a packer board to achieve a required height in ProTherm Quantum ‘Hybrid’ systems.

For use in the ProTherm Quantum VIP Insulation System installed over any BBA Certified Inverted roofing systems.

ProTherm XPS Layer is a rigid, closed cell type Extruded polystyrene board with integral high density skin. ProTherm XPS Layer has a Zero Ozone Depletion Potential (ODP), a Global Warming Potential (GWP) of less than 5 and an A rating in accordance with the Green Guide to Specification.


Apply ProTherm XPS Layer parallel to roof perimeter long edges. Stagger end joints.

Lay ProTherm XPS Layer with edges in moderate contact without forcing.

Cut ProTherm XPS Layer to fit neatly to perimeter blocking and around penetrations through roof, when using a 2nd layer stagger joints of insulation from first layer.

Cut ProTherm XPS Layer to create an opening large enough to accommodate the installation of either a domical or flat grate into a flanged rainwater outlet.

Apply no more ProTherm XPS Layer than can be covered with aggregate ballast/concrete roof pavers/green roofing in the same day.

Keep ProTherm XPS Layer minimum 75mm from heat emitting devices, and minimum 50mm from sidewalls of chimneys and vents.

Description  Value
Appearance Grey Skin
Board Width 600mm
Board Length 1250mm
Board Thickness Single Layer 30/40/50/80/100/120/130/140/160/180/200/205mm
Board Thickness Double Layer 60 (30+30), 70 (30+40), 90 (40+50) 
Edge profile 15mm shiplap edge, rebated on all 4 sides* 
Compressive strength at 10% compression  300 kPa
Thermal Conductivity 50mm 0.030 W/mK
80-200mm 0.031 W/mK

*Panel to be cut to required infill size 


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