1.Based on Pulping Process

Fully Mechanical (GW, PGW, RMP) Mechanical & Thermal (TMP) Semi-mechanical, semi-chemical (CTMP) Semi chemical (NSSC, Cold Soda) Fully Chemical (Sulfite, sulfate) Soft Cook Fully Chemical (Rayon, viscose)

2. Based on Raw Material

Wood (HW, SW) Agricultural Residue (Straws) Annual Plants & Grasses (Hemp, Jute, Kenaf, Bamboo) Rags Recycled or secondary Fiber Deinked

3. Based on Bleaching

Totally Chlorine Free (TCF) Elemental Chlorine Free (ECF) Chlorine Bleaching (Chlorine gas & Hypochlorite) Oxygen/Ozone Bleached. Unbleached

4. Based on Yield

Very High Yield (>95%) - GW, PGW High Yield (85-95%) - RMP, TMP Medium High Yield (65-85%) - CTMP, NSSC, CMP Medium Yield (45-65%) - (Sulfite, Sulfate) Medium Low Yield (35-45%) Straw, Grass, Bagasse chemical pulp Low Yield (<35%) - Rayon, viscose

5. Based on Fiber Length

Long Fiber Pulp (>10mm) - Cotton, Hemp, Flax, Jute Medium Fiber Pulp (2 - 10mm) - Northern S/W, H/W Short Fiber Pulp (< 2mm) - Tropical H/W, straws, grasses

The three most important Parameters which defines the pulp are. 1.) Fiber Length, 2.) Brightness, 3.) Pulping process used. e.g

WEHRHAHN plants (equipment)

Individually designed to meet your requirements.

Wehrhahn supplies plants with capacities from

2 - 20 t/h. The fibre cement production process has continuously been further developed to reduce

material and energy consumption figures. Process related cut-off materials and rejects

are immediately recycled in the process. Surplus water runs through a treatment plant and

returns into the production process.

For the production of the large variety of sheets, two technologies have proven to be suitable:

Air cured (CC) fibre cement sheets are perfect for roofing products and all applications

where the sheets are directly exposed to harsh weather conditions. Autoclaved (CCA)

sheets are the choice for façades, cladding and all interior applications.

• CC = Cellulose Cement Sheets

CC sheets are manufactured from cement and fillers. A blend

of virgin cellulose and synthetic fibres such as PVA or PAN are

used as fibre reinforcement.

• CCA = Cellulose Cement Autoclaved Sheets

CCA sheets are manufactured from cement, finely ground

silica sand and some additives.

Virgin cellulose is used as fibre reinforcement.

Compressed sheets

CC and CCA sheets can be compressed in a single sheet or stack press. Pressing increases the sheet density

and strength. The sheet resistance towards freeze/thaw conditions is enhanced. Pressing provides a very

smooth surface finish.

Which technology for which product?

CC sheets for CCA sheets for

Roofing

(corrugated or flat)

Lap siding

(with timber pattern, wood grain or smooth)

Façades Façades

Fencing Fencing

- External base for plaster

- All internal applications

Plant capacity range

Market Capacities t/hour Number of sheeting machine cylinders Sheeting machine width

Small 2 - 3 2 single width

Medium 8 - 10 4 - 6 single width

Large up to 20 5 double width

Note: Other capacities upon request.

WEHRHAHN leading in autoclave technology

WEHRHAHN is the global leader with superior technology to manufacture machines for

the production of autoclaved calcium-silicate products, such as fibre-cement sheets,

aerated concrete blocks and panels, insulation boards, etc.

Sand grinding, sand slurry dosing as well as autoclaves, automatic pressure control and

automatic condensate discharge are equally vital parts of Wehrhahn‘s know-how.

Production of fibre cement sheets in Wehrhahn plants

State-of-the-art highly efficient machines, plants and technologies for the production of

fibre cement sheets

Material Preparation

Lowest production costs due to highly efficient machines and technologiesThis includes the material preparation with

sand grinding mill, sand slurry silos as well as openers and refiners for cellulose.

Dosing and mixing / sheet production

Wehrhahn's computerized smart dosing and mixing plant "WECOMIX" prepares a slurry which is further diluted

and fed into the sieve cylinder sheeting machine. Thin layers are formed on 3 to 6 sieve cylinders and transferred

onto a felt. The layers are accumulated around the forming roller until the preset thickness has been reached and

the sheet can automatically be cut off.

Thickness control

Wehrhahn's advanced self-adjusting sheet thickness control system ensures minimum thickness variations. This

saves material (no overthickness) and reduces rejects (underthickness) which finally increases plant output and

economy for Wehrhahn customers.

Cutting

Wehrhahn supplies the full range of downstream machines including cutters for all purposes such as cutting and

punching press, guillotine knife cutter, water jet cutter or just circular knife cutter.

Pressing

Wehrhahn's single sheet presses for corrugated or embossed roofing sheets or stack presses for high

compressed flat sheets improve the sheet density and quality - an important factor for improved frost resistance.

Autoclaving / calcium-silicate

Wehrhahn provides all equipment and extensive know-how for the steam curing technology as this is also

process-relevant for Wehrhahn's AAC (autoclaved aerated concrete) block and panel plants. Wehrhahn's

automatic autoclave system (WACO) allows easy control of the complex chemical process in the autoclave.

Coloured sheets

If your market requires more beautiful roofing, Wehrhahn also provides a range of equipment for colouring

sheets, such as through-pigmented, top layer, pigmented or surface paint-coated. Paint coating increases beauty

and improves quality.

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Startpage > Fibre Cement > Products

Fibre cement sheets for façade, roof and internal application

A unique and versatile building material

Few building materials offer a combination of architectural scope and strong technical specification as convincing

as fibre cement cladding and roofing.

Fibre cement combines strength with ease of handling and stylish versatile colour options.

Fibre cement gains its impressive strength in a special manufacturing process where thin layers of fibre cement

are laminated and compressed under high pressure followed by air curing or autoclave curing.

A major advantage of fibre cement is its ability to resist all kinds of weather conditions. Frost and thaw, heat, hale

or rain do not pose a threat to fibre cement. Inside buildings fibre cement is applied as backer board in wet areas

or for dry walls in heavy duty applications where fire resistance and strength are the dominant requirements.

Architects love fibre cement, elegantly finished with a wide range of colours to select from. Sheets are easy to

install and can be cut to any required dimensions or edge details.

Fibre cement sheets are used for residential, industrial and agricultural applications. Its appearance and

advantageous characteristics make it the ideal material for the following applications:

External cladding / caçades / fencing

Flat sheets in various sizes and colours (coated, pigmented or painted), as lap siding or planks, preferably with

timber pattern have conquered many markets.

Applications:

• façades

• cladding / siding

• ridges, eaves and soffits

• fencing

• base for plaster / stucco

Façades

Façade sheets are a durable alternative to stucco and

• can be applied even during heavy frost when stucco cannot be applied

• can cover and protect exterior wall insulation

• are used for exterior wall cladding of cottages and townhouses, beautiful (naturally looking) wood

grain planks (sidings) and provide architectural beauty

For the surface treatment of fibre cement, many options and colours are applicable.

Internal cladding

Flat sheets which offer unsurpassed properties in fire resistance, dimensional stability, water resistance and

acoustical properties can be used in a wide variety of different applications.

Applications:

• internal lining in wet areas

• perfect base for ceramic wall tiles (backer boards)

• partitions

• fire resistance application in hospitals or kindergarden

• floors and ceilings

Fibre cement allows water diffusion in both directions. Water can be absorbed and easily be released. This

results in convenient climatic conditions inside buildings.

Roofing, corrugated roofing and façades

Fibre cement has been used as a roofing material for decades. Here small sized shingles / slates and corrugated

sheets have proven to be the best choice. Different sizes and colours to meet the many individual requirements

can be found in the market.

Products:

• shingles / slates, mostly highly compressed and painted, stand for architectural beauty

• corrugated sheets, painted in numerous colours, may be used for external cladding or fencing

applications

Asbestos Roofing

The last 20 years has seen growing concerns over asbestos and many property owners are faced with the dilemma of what to do once their old roof starts to deteriorate and leak. Many roofs have been removed in the past and replaced due to health concerns whilst others have been replaced with better insulated roofing materials.

What is Asbestos Cement?Asbestos cement is a mixture of cement and asbestos (usually about 10-15% of the total product) forming a hard material often used as corrugated roofing on sheds, garages, farm buildings and industrial units. Asbestos cement usually contained white asbestos (chrysotile) but older types may contain blue (crocidolite) or brown (amosite).

The type used is not really important as all asbestos is hazardous, although asbestos cement does not release many fibres and is relatively low risk. It is sometimes difficult to tell the difference between an asbestos cement product and a low-density insulation board. Where the product has been used as a roofing or cladding product open to the weather, you can be confident that the product is asbestos cement.

Safety firstIf your roof is made with Asbestos Cement, a licence is not needed to remove it. However, in compliance with HSE, All Roofing and Building is highly experienced in handling the product and fully aware of the strict guidelines that must be followed to remove and dispose of the product correctly. A licensed contractor is only needed to work on High Risk Asbestos such as pipe insulation or insulation panels – NOT on Asbestos cement which is considered much less dangerous.

It is still important to take precautions with handling old asbestos sheets and protective overalls and face masks are recommended. Cutting is considered hazardous and therefore not recommended.

Whilst the HSE do recognise the hazard of Asbestos in fibre cement sheets, it is far more likely that serious dangers come from walking on the roofs without protection from falling through them.

Many serious accidents in the past have arisen through people falling through them as the asbestos sheet can break under the persons feet. With Health & safety now being a formidable force any activity on a asbestos roof should be done only after safety netting has been erected. So even if you have roof-lights to be changed or minor repairs are needed this is essential before any work or inspection is carried out.

Should all asbestos sheets be dumped?

With so many agricultural buildings in use there has to be a call for using the roofing sheets again as many are perfectly good when stripping off roofs.

The main problem with re-using old asbestos sheets is that they get slippery when they are wet, dry conditions would be needed to refix them but then again any work on old roofs should be done in good conditions. However in a world that considers recycling as a good thing it has to be right that this should be done whenever possible. Other benefits are that it stops old buildings that have had repairs from looking like patchwork quilts, due to the use of new sheets.

Occassionally we have in stock used fibre cement sheets which we use for repairs, these sometimes come in when newish farm buildings are changed to be used for industrial.

How experienced are we at strip and re-sheeting asbestos roofing?

Well, we have stripped literally 1000′s of tons off and our biggest job to date was a 10,000 sq meter double skin off with a double skin tin replacement. We are always interested in anything bigger or smaller re-sheeting jobs than that..