35mm STEICO Universal Wet Wood-Fibre Insulation Board - Sarking and Sheathing Board - 1880mm x 600mm
35mm STEICO Universal Wet Wood-Fibre Insulation Board - Sarking & Sheathing Board - 1880mm x 600mm
Length: 1880mm
Width: 600mm
Thickness: 35mm
Board coverage: 1.13m2
Density: 270kg/m3
Weight/m2: 9.45kg
Weight: 10.68kg
Thermal Conductivity: 0.048W/mK
R-Value: 0.7m2K/W
Fire Rating (Reaction to Fire): E
35mm STEICO Universal Wet is a high-density, rigid wood-fibre insulation board designed for both roof and wall applications. Manufactured using the traditional Wet Process, it relies on the wood’s natural lignin to bond the fibres together, creating a robust, vapour-open board that is exceptionally eco-friendly. STEICOtherm Universal is a multi-purpose sarking and sheathing board designed to wrap the exterior of a building.
CHARCTERISTICS
- Weather Resistance: The boards are impregnated with natural paraffin (wax) during manufacturing. This allows them to serve as a temporary weather layer for up to four weeks during the construction phase, protecting the structure before the final roof tiles or cladding are installed.
- High Density & Strength: With a density of approximately 270kg/m3, it is much harder than "Therm" boards. This high density provides incredible compressive strength (200kPa) and superior sound insulation.
- Tongue & Groove (T&G) Profile: Typically supplied with a precision-engineered T&G profile on all four sides. This creates a wind-tight, interlocking "rain-screen" layer that eliminates thermal bridging at the joints.
- Vapour Permeability: Like all Steico wood-fibre products, it is highly breathable. It allows moisture from within the building to escape safely, reducing the risk of interstitial condensation and rot in timber frames.
APPLICATION
- Roof Sarking: Installed directly over rafters. It provides a continuous insulation layer that keeps the rafters warm and dry while significantly reducing summer overheating.
- Wall Sheathing: Fixed to the outside of timber frame studs. It replaces traditional OSB or plywood sheathing, providing both structural racking support and a breathable thermal wrap.
- Renovation: Excellent for over-insulating existing roofs or walls to meet modern building regulations without losing internal space..
CERTIFICATIONS

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