9mm Windstopper Extreme Fire Resistant External Sheathing Board (1200mm x 3000mm) is a vapour permeable fibre-cement based building board with a 60/60 fire rating, an ideal solution for exterior walls used as a temporary cladding.

Windstopper Extreme by Cembrit is a non-combustible, vapour permeable cement based building board that has a very low vapour transmission resistance, enabling moisture from inside the building to pass through.

The board consists of grey cement and limestone filler, reinforced with a specially selected fibre material that can absorb and release moisture without affecting the durability, strength or performance of the board.

Cembrit Windstopper Extreme is available in two thicknesses 4.5mm and 9mm, the boards can be scored and snapped making them an ideal choice for rapid and dust-free installation.

Both thicknesses provide good acoustic insulation properties, when installed according to Cembrit installation instructions, Cembrit Windstopper Extreme will function as a temporary facade for up to 12 months.

Windstopper Extreme can accept insulation being placed against the board on the warm side of the building, whilst acting as a fire break against any blaze in the ventilation cavity behind the rainscreen.

This special Cembrit panel has been designed for use as a sheathing board in rainscreen facade cladding application and is BBA Approved (no. 21/5885). 

As part of a non-load bearing vertical building element Windstopper Extreme 9mm will provide up to 90/90 minutes of fire resistance when exposed to fire from one side.

This board consists of natural materials and variations may occur in the product colour or other characteristics from board to board.

Cembrit Windstopper Extreme has been tested in accordance to BS EN 1364-1:2015 (BS 476-22:1987).

Specification:

Thickness: 9mm

Width: 1200mm 

Length: 3000mm

Board Coverage: 3.60m2

Density: 1300kg/m3

Surface Front Face: natural rough surface

Surface Back Face: natural rough surface

Durability (Life Expectancy - Minimum): 15 years

Fire Reaction: Class A2-s1,d0, Non-combustible

Cembrit Windstopper Extreme 9mm External Sheathing Board Features:

 · Non-combustible

 · Highly durable.

 · Breathable.

 · A2 fire protection class.

 · Fibre-cement based.

 · Moisture and mould resistant.

 · Can be used as a wind barrier.

 · Vapour permeable board.

 · Natural rough surface.

 · Windproof membrane for exterior walls.

 · Sustainable solution.

 · Resistant to harshest weather and climate conditions.

 · 15 Year Cembrit Warranty.

 · Can be used as temporary facade protection for up to 6 months.

 · Resistant towards both rot and fungal growth.

9mm Cembrit Windstopper Extreme External Sheathing Board Installation Guidelines:

 · The boards are fixed to the wall frame with screws or clout nails spaced 200mm along all edges and 300mm elsewhere.

 · The distance between screws or nails and the board edges shall be minimum 15mm, and distance to the corners minimum 70mm.

 · The screw or nail heads shall be level with the board surface.

 · The diameter of clout nail heads shall be minimum 8mm.

 · If other types of nails with smaller heads are applied the nails shall be covered by a tape in the same way as for joints between boards.

 · Connections to foundations, window and door openings, roof and wind barrier penetrations shall follow the principles shown in relevant Building Research Design Guides.

 · When used as sheathing and wind barrier in floors over crawl space foundations Cembrit Windstopper boards are fixed with screws spaced 200mm along all edges.

 · The distance between screws and the board edges shall be minimum 15mm, and distance to the corners minimum 70mm.

 · Penetrations of the wind barrier layer in structures with a classified fire resistance shall have a documented fire resistance performance which do not reduce the fire resistance performance of the boards.

 · All joints between boards shall be sealed with Cembrit Windstopper Tape.

 · The board surface shall be dry and free from dust before the tape is applied.

 · Minimum effective width shall be 50mm.

 · At tape joints the overlap shall be minimum 25mm.

 · The boards shall be stored on a level support in a dry place.

 · If stored outside the boards shall be protected from moisture, dirt and mechanical strain by a ventilated tarpaulin.

You can order free Cembrit Windstopper Extreme External Sheathing Board samples here.

*Further information may be found in our Downloads section.

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