Wood-cement composites

Product description

Wood-cement composites (also known as fibre-cement) are produced by mixing small pieces of wood with cement under pressure. They are produced in a range of shapes and sizes. Non-structural applications include acoustic ceiling tiles, siding and roadside noise barriers. Structural uses include concrete-filled insulating forms.

Wood-cement boards
Wood-cement boards for siding
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Technical information

Wood-cement composites can be made from a variety of different-sized and -shaped wood elements. A porous, low-density panel is made from wood wool (long thin slivers of wood), while a product more similar to conventional particleboard is made from wood particles and shavings. Sawdust and fibres can be used to make moulded products.

Wood-cement composites use much less wood than other wood panels, and in some instances the wood component of the product can be considered as filler to decrease the amount of cement used. Some wood species are not suitable because sugars and other chemicals contained in the wood inhibit the curing of the cement.

Wood-cement composites have good moisture resistance and dimensional stability as long as the edges are sealed, but are more difficult to cut and fasten than traditional wood-based composites. They have very good acoustic and insulating properties.

Markets

The largest market for wood-cement composites in North America is exterior siding: fibre-cement is used for siding in approximately 15% of all new houses and the use is growing, since fibre-cement outperforms vinyl siding in terms of durability, maintenance and ease of painting.

However, there is a high degree of variation in the characteristics of wood-cement products. Each manufacturer has proprietary processes and formulations, and the products of some companies significantly outperform those of others.

In the past, asbestos was used to help bind the fibres with the cement. Older wood-cement ceiling tiles must therefore be removed with caution.