What Are Fibre Cement Roof Sheets?

What are Fibre Cement sheets?
Fibre cement sheets are a corrugated sheet material used for roofing and cladding. Sometimes referred to as undulated sheets they have a wavy profile which come in different sizes colours and forms. They are a strong durable roof sheet used in agriculture, industry and residential properties. Lending themselves to residential dwellings in the countryside due to their ability to fit in with the rural landscapes.

They are provided in sheet lengths of up to 3m, and are commonly provided in a profile 6, sometimes referred to as Big 6, or a 6” inch profile although others are available such as the smaller profile 3, and unique profiles such as the Eternit Urban pro.

What are fibre cement sheets made from?
Fibre Cement roof sheets are made from cement with a mixture of synthetic and natural fibres, which is what gives the roofing sheet its strength, insulative, and sound absorbing properties

What can fibre cement sheets be used for?
Profiled fibre cement sheets are very versatile and can be used in part for most buildings, but there more common are listed below, this is not an extensive list as the roof sheets can be used on any dwelling, or property whether it be business, industry or leisure providing the roof pitch is able to be accommodated.

Agricultural buildings / Barn roofs/ Stables / Cow shed.
Fibre cement sheets produce less condensation than metal or fibre cement sheets due to the material being more absorbent that the smooth finish of metal and GRP. Having less condensation results in less dripping from the roof internally, which can help with animal wellbeing and stress level. Additionally, there is less noise produced from rain hitting the roof which also aids in animal wellbeing.

Contemporary/ Modern homes/Residential
As fibre cement sheets can be used both for pitched roofs and for cladding this makes them a versatile addition to your choice for building attractive dwellings. Offering a choice of colours, having good insulative properties and sound reduction make them a great choice of roofing material for dwellings.

Storage sheds / warehouse roof covering
Being less prone to attack from chemical, low maintenance and producing less condensation fibre cement roof sheets are all great attributes for warehouse or storage roof. Being in common industry areas where corrosives may be present in the air and preventing the stored items from being water damaged.

Education / Schools / Colleges.
Fibre cement sheets are a cost-effective solution offering great insulative properties, and sound absorption making hem ideal for educational facilities and noisy sports halls.

Why use Profiled Fibre cement sheets?
-Low maintenance
Fibre cement profiled sheets are inherently a low maintenance product, needing only to be simply cleaned with soap and water for the lifespan of the product.

-No rust rot or corrosion
Fibre cement does not rust, there is no risk of wholes forming, or any chemical reactions, making it safer to be on the roof, and less maintenance.
-Fibre cement roof sheets are Quick and easy to install and fix
Being a sheet material, rather than slats, like traditional cladding, or individual pieces such as roof tiles result in fibre cement roof sheets having a much quicker install time as each roof sheet will cover a large area.

-Cost effective
Profiled fibre cement roof sheeting is very competitive when compared with metal, particularly when looking at natural grey.

-Resistant to chemical attack
Due the to material fibre cement roof sheets have a very low to no reaction to most common chemicals making them ideal for use in factories, and industry.

-Excellent noise and thermal insulation
Due to the fibres within the sheets and general make up of fibre cement roof sheets, they are inherently good at absorbing sound and keeping heat

-Wide Product Colour Range.
With plenty of choices for colour, fibre cement sheets can suit a variety of projects and satisfy local councils in terms of having to fit in with the surrounding area.

-50 year lifespan
Fibre cement sheets are a robust long life product, with a 50 year lifespan you can get the job done once, and not have to do it again for a substantial amount of time, making it a solid cost effective solution for roofing and cladding.

-Fire performance Class A2 to BS EN13501-1, SAA and class 0
When constructing a roof for any reason, the fire rating is always a consideration, whether that be fibre cement sheets, metal roof sheets, roof tiles, or anything else.

What Profile should I be using and why?
When choosing a profile for sheets the primary reason will be the water load that the roof must take. A roof that is expected to hold more water usually requires a larger profile roof sheet. This is usually considering three factors.
-The roof pitch
A low pitch roof results in the water running off at a slower pace, which will result in the roof holding the water for longer, resulting in more water weight present on the roof at any one time. In general, a lower pitch will require a larger roof sheet profile. Steeper pitched roofs can use a smaller profile such as the urban pro fibre cement sheets.

-The roof size
The larger the roof, the more water the roof can hold, which can result in leaning towards a larger profile sheet as this enable faster run off the water due to larger channels for it to travel. In general, a larger roof size will require a larger profile sheet. Smaller roofs can accommodate smaller profiles such as the urban pro fibre cement sheets.

-The geographical location
This is simply the amount of rainfall that is expected for an area, and how heavy it can rain, which has an obvious relationship with how much water the roof can be expected to carry. In general, locations that get more rainfall will require a fibre cement roof sheet with a larger profile.
-Matching in
Sometimes you will be replacing a broken or damaged roof sheet, in this instance you are lead by the profile that is already there, if this is the case it is a good idea to measure the sheets profile buy measuring the height of the corrugations and the distance from the centre of one corrugation to the centre of the next. Or if you have a sheet on the ground you can use that to create a pattern, to share when looking for sheets. It’s a good idea to be armed with this information when shopping to enable the representative to help guide you to the right profile sheet.

-Roofing material classifications (non-fragile)
Sometimes particularly for a roof with lots of roof lights, or a factory roof that may have other elements for extraction, roof access may be expected to be relatively frequent and so the roof must be specified as non-fragile this is purely for the health and safety perspective.

Fibre Cement Sheets Verses Metal Roof

Fitting fibre cement sheets
- Lay the first roof sheet at eaves, at one end of the building with the smooth side facing up. The head of the sheet should be positioned 50mm from the centre of the purlin and the sheet should be square to the framework

- The base of the sheet can then be fixed to the first purlin, Typically self drilling screws can be used for timber and light gauge steel structures. The fixings will have wings which will oversize the whole enough for the 2mm movement gap.

- The sheets are fixed using a simple method of 2 fixings per purlin per sheet and are fixed through the peak of the corrugation

- In regular conditions a 150mm end lap is required, but increased lap is required depending on location so please double check this.

- Lay the second sheet upslope overlapping the bottom sheet by the required overlap, to avoid a building up of fibre cement at the overlaps a diagonal cut is made called a mitre, the mitre measurement is dictated by the end and side lap. Mitre cutes should be made at ground level using a hand saw or low speed reciprocating power saw.

- Before getting to the ridge, it is good practice to install the opposite side first run as well, so ensure the corrugations on the ridge will align.

This is a simplified installation process, as there are other elements of the roof to consider including roof lights, barge board (which is used up the verge) and a host of other elements to consider when using the sheets vertically for around windows for example.
We are able to provide full quotes for fibre cement roof sheets please get in contact for more information.