The strongest underlay in its class/weight range, the VP400 plus LR by Glidevale Protect is a type of roof underlay that boasts high vapour permeability, making it ideal for use in all pitched roofs. Despite having the lowest vapor resistance among Type LR roofing underlays in its class, it maintains complete air tightness and exhibits impressive durability, toughness, and resistance to UV and heat.

The air tightness of buildings and homes continues to improve due to better workmanship and enhanced practices. However, it is not recommended to have uncontrolled air movement within the structure, such as through a roof underlay that lacks proper air barrier or vapour control layers.

FEATURES & BENEFITS:

• High vapour permeability but complete airtightness
• Completely watertight >7.0m water resistance
• Exhibits durability, UV and heat resistance
• Suitable for use as a temporary roof covering
• Unrestricted use for wind uplift in all exposure conditions in the UK and Ireland
• Suitable for zones 1-5 at 345mm batten gauge
• Aids in the prevention of condensation risk in the roof space to BS 5250 and NHBC requirements
• 50m length x 1.5m width
• Roll size of 75m²
• Weight of 170gsm (roll weight of 14.81kg)

A crucial function of a roof underlay is to manage wind load pressures on the roof. To obtain this, the underlay should possess adequate mechanical properties to safely deflect wind load pressures over the structure. Another crucial property is that the underlay should be air and water tight. If the underlay is leaky or air-permeable, air can penetrate the membrane. As a result, it becomes tricky to withstand maximum wind load pressures and driving rain without additional surface treatments.

VP400 plus LR is suitable for use as a temporary roof covering. It has unrestricted use for wind uplift in all exposure conditions in the UK and Ireland, and it is suitable for zones 1-5 at 345mm batten gauge.