Cement consists of the following materials, by their volume ratios, after a hardening period of 28 days:
- 40 % Bonding agent
- 11 % Additives including high quality pigments
- 2 % Reinforcing fibres
- 5 % Process fibres
- 12 % Water
- 30 % Air
The bonding agent in the products is Swiss Portland cement. This raw material is sintered from limestone and clay marl, and is proportionally the most significant of the raw materials.
Additives such as powdered lime improve certain characteristics of fibre cement, and provide uniform product quality. Micromized pigments - mainly iron oxide and titanium - in a great variety of shades.
Synthetic organic fibres made of poly-vinyl-alcohol are used for reinforcement. These are similar to fibres found in textiles and fabrics.
Process fibres are cellulose fibres, such as those used in the paper industry. Recycled waste paper is used to some extent.
The water that remains in the product after the hardening phase then produces additional strength throughout the whole life of the product.
Air is present in the form of microscopically small pores. These act as expansion spaces when water freezes, and prevent frost damage. They create a moisture-regulating construction material that actively breathes.
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