FAQs – frequently asked questions
Here you will find answers to frequently asked questions about fermacell® products, their applications, installation and maintenance.
General
fermacell® fibre gypsum boards and fermacell® flooring elements can be used on all wall and floor surfaces subject to normal domestic use. These surfaces are exposed to splash water only briefly and to a slight to moderate degree.
In areas of the domestic bathroom exposed to water (the entire floor area, and walls behind or above baths and showers), a waterproofing layer is required on the board surface. fermacell® offers a tested system for this purpose.
Cement-bonded Powerpanel boards
fermacell® Powerpanel H2O is suitable for wall and ceiling constructions in domestic wet rooms (bathrooms, showers) as well as in public areas (swimming pools, wellness areas, sanitary facilities) and commercial areas (e.g. commercial kitchens, breweries, dairies). In domestic settings, it is sufficient to additionally seal fixing points and joints. Full-surface waterproofing of the board surface is not required.
For use with fermacell® Powerpanel H2O in public areas, the specific requirements regarding the choice of substrate, the necessary corrosion protection and professional waterproofing must be observed.
Detailed instructions on planning and installation can be found in the installation guide.
James Hardie does not offer a direct delivery service for fermacell™ products. Delivery to site is arranged by specialist building materials suppliers.
You can find a building materials supplier near you in the Find a dealer.
No, fermacell™ adhesives do not contain any solvents. This applies to fermacell™ joint adhesive, fermacell™ joint adhesive greenline, fermacell™ screed adhesive and fermacell™ Therm™ adhesive. Solvents are not required for this process. fermacell™ Greenline Screed Adhesive and fermacell™ Therm Adhesive are dispersion-based adhesives that cure through the release of water. No solvents are required here either. Certificates from the ECO-Institut Köln are available for all adhesives in the download section.
Unfortunately, we cannot make any general statements.
Customers are kindly requested to contact a local dealer. As the manufacturer, we are unfortunately unable to offer direct sales or collection from our premises.
However, our products are available from specialist building materials retailers. If a product is not in stock at your local store, the retailer can order it from us at any time.
You can find a building materials supplier near you here.
No. fermacell® fibre gypsum boards consist of 80% gypsum and 20% paper fibres made from recycled waste paper. After water has been added, these two raw materials are pressed under high pressure into sturdy boards without the use of any additional binders.
The composition and manufacturing process have not changed significantly since the panels were invented in 1970: In the case of gypsum, the natural gypsum previously used has been partially replaced by environmentally friendly flue gas desulphurisation (FGD) and recycled gypsum, whilst cellulose-based substitute fibres have been added to the paper fibres. In fermacell® Firepanel boards, some of the cellulose fibres are replaced by rock wool fibres to achieve a higher level of fire protection.
The fermacell™ joint filler has also always been manufactured without fibres (which may contain asbestos). The reinforcing agent used here is methylcellulose (the base material in wallpaper paste).
All other products were developed and launched on the market after 1980. By that time, asbestos had already been banned.
The technical specifications and values required for the design of structures can be found in a European Technical Approval (ETA) and/or a national approval. All European and national approvals are available in the downloads section.
For any enquiries regarding orders, deliveries or invoices for our products, please contact our customer service team.
James Hardie Europe manufactures fermacell® fibre gypsum boards at four production sites. The ETA 03/0050 product approval for fermacell® fibre gypsum boards applies to all production sites. The technical specifications listed there in must be strictly adhered to. Furthermore, fermacell® fibre gypsum boards are tested by the ECO-Institut. These reports also evaluate the boards from all four plants. Due to the raw materials available in different regions, colour variations may occur; these do not represent any loss of quality.
You can find the material approval in the downloads section.
You can obtain test certificates and reports via Telephone 0800 3864 001 or simply use the Contact form on our website.
Installation
No, this method of fixing is not permitted.
Due to the properties of the material, the panel can only be installed on a metal or timber substructure, depending on the specific application.
No, this method of fixing is not permitted.
Due to the properties of the material, the panel can only be installed on a metal or timber substructure, depending on the specific application.
fermacell™ drywall screws (countersunk screws) are specially designed for fixing fermacell® fibre gypsum boards to timber and metal substructures.
The thread on these screws does not extend all the way to the head (as is the case with many no-name plasterboard screws), but ends approximately 8 mm before the surface of the screw head. This allows the thread to cut its own path through the fibre gypsum board and press the board tightly against the substructure. With no-name screws, there are often surface irregularities and misalignments in the board joints. Quick-fit screws for plasterboard (trumpet-head screws) are also unsuitable, as the large head does not countersink into the solid fibre gypsum board. This results in unevenness or the board edges breaking off.
fermacell® gypsum fibreboards have a stamp on the back showing approval and manufacturing details.
They are manufactured to be homogeneous and have the same properties on both sides. However, due to manufacturing tolerances, the reverse side of the panels may have unevenness and imperfections in the finish. The embossing on the reverse side may also show through the coating. It is therefore advisable to install the panels with the unstamped side facing outwards. If the reverse side is nevertheless installed facing outwards, this does not pose a structural problem. In this case, the reverse side should be treated with a fine filler before further coating.
Cement-bonded fermacell® Powerpanel boards
fermacell® Powerpanel boards feature embossing on the front. This also marks the centre of the board and makes it easier to fix in place. fermacell® Powerpanel boards have a very smooth front and a back that is usually sanded and rougher. Although the board has a homogeneous cross-section, it is therefore recommended that it be installed with the correct side facing outwards. The same applies here: if the reverse side is nevertheless installed facing forwards (rough surface facing forwards), this does not pose a structural problem. If a smooth surface is desired, the rough surface should be smoothed using fermacell™ Powerpanel fine filler.
fermacell® fibre gypsum boards are hydrophobic-treated at the factory. It is not necessary to apply, for example, a wallpaper primer (unless required by the manufacturer of the wallpaper paste), as the fermacell® surface cannot be damaged when the wallpaper is stripped due to the homogeneous board structure.
With certain topcoats, such as silicate paints, textured plasters or tiles, a primer may be required to control the absorbency of the substrate. In such cases, the manufacturer’s instructions must be followed.
Sustainability
If you can't find what you're looking for here, please feel free to contact your sales representative at any time.
We are committed to taking responsibility for nature and the environment. That is why we support you in collecting your single-type fibre gypsum board offcuts on site. Our partnership with local businesses enables us to optimise processes and makes taking part incredibly easy.
Yes. fermacell® fibre gypsum products are recyclable and can be returned to the material cycle after use. This requires that the materials are sorted correctly; the boards must not be contaminated with foreign substances.
Positive. Thanks to their high mass and heat storage capacity, fermacell® fibre gypsum boards help to maintain a stable indoor climate and provide heat protection in summer.
Yes. fermacell® fibre gypsum boards are vapour-permeable, help regulate humidity and contain no volatile organic compounds. This ensures a comfortable and healthy indoor environment.
In the case of structures without a visible surface and with butt joints, it is possible to carry out a dismantling process using materials of the same type.
No, fermacell® fibre gypsum products do not require any additional protective coatings. This results in fewer potential pollutants and makes it easier to recycle them as a single material.
You will usually need environmental product documentation, such as an EPD (Environmental Product Declaration), so that the product can be assessed correctly for building certification. Further requirements depend on the specific building certification scheme.
Yes. fermacell® fibre gypsum products support certifications such as BREEAM, and LEED, as they meet environmental and health requirements. The relevant requirements and the overall project, including all building materials used, are always decisive for obtaining the relevant certification.
Yes, we have the relevant certificates for many of our products. These can be found directly in our downloads section.
Constructions using fermacell® fibre gypsum products are more sustainable because they meet high standards of fire, sound and structural protection whilst using fewer materials, thereby conserving resources and reducing CO₂ emissions.
Yes. fermacell® fibre gypsum boards are the ideal complement to timber structures, as they combine fire protection, sound insulation and negative CO₂ storage (cradle-to-gate) with environmental benefits, making them perfect for sustainable construction methods. Thanks to the high durability of our products, CO₂ emissions are reduced to a minimum over the entire life cycle.
You’re doing your bit for the environment, because fermacell® fibre gypsum products reduce CO₂ emissions and conserve resources thanks to recycled materials such as paper fibres. Our boards are produced in a resource-efficient manner, are highly durable and perform well, which leads to reduced material consumption. At the same time, you are avoiding energy-intensive natural gypsum mining and opting for an overall highly sustainable material cycle solution.
The gypsum used in fermacell® is mainly derived from flue gas desulphurisation gypsum, a by-product of flue gas cleaning, and is therefore considered to be relatively sustainable. However, the extraction of natural gypsum is also carried out in a sustainable and resource-efficient manner and therefore does not pose a problem.
The main components of our fermacell® boards – gypsum and paper fibres – are sourced primarily from regional suppliers and recycling processes. This reduces transport distances and conserves natural resources.
Yes. fermacell® fibre gypsum products are made almost entirely from natural raw materials. The gypsum is largely sourced from flue gas desulphurisation, where it is obtained as a by-product, or from our own recycling processes. The paper fibres used are made entirely from recycled material. Production is resource-efficient and carried out in accordance with high environmental standards.
No! fermacell® fibre gypsum boards are free from harmful substances, contain no VOC emissions and pose no health risks when used indoors. They are also suitable for sensitive areas such as children’s bedrooms or schools.
The Institut Bauen und Umwelt E.V. (IBU) has had the life cycle assessment of fermacell® fibre gypsum boards and fermacell® flooring elements verified by independent experts. According to the issued EPD (Environmental Product Declaration), fermacell® products save CO2 over their entire life cycle (from raw material and energy extraction through the actual manufacturing phase of the boards to the end-of-life phase including disposal) and are free from substances hazardous to health.
Extremely durable. The panels are moisture-resistant, dimensionally stable and can withstand mechanical stress. A long service life means fewer replacements and therefore a lower environmental impact.
Wall and ceiling
Cross joints should be avoided when installing fermacell® fibre gypsum boards, fermacell® Powerpanel boards and fermacell® flooring elements.
When laying cross joints, there is no interlocking. The intended "staggered bond" – which is also common in masonry construction – results in greater strength. The risk of through-cracks is reduced.
No.
fermacell® gypsum fibreboards are an ideal material for all aspects of dry interior finishing and can be used universally in construction projects from the basement to the roof. Due to their material composition (gypsum and paper fibres), they are a gypsum-based building material best suited for interior use.
For outdoor use, cement-bonded fermacell™ Powerpanel products should be used in accordance with the relevant building and structural requirements.
The structure of fermacell® fibre gypsum boards and fermacell® Powerpanel boards is the same in both the longitudinal and transverse directions. They can therefore be installed either parallel or perpendicular to the substructure.
To achieve optimum strength, it is nevertheless advisable to lay the longer sides of the panels end-to-end on the substructure and the shorter sides at right angles to them. In the case of single-layer cladding, these should then be glued down where possible.
These specifications apply to both wall and ceiling structures.
The method of fixing fermacell® gypsum fibreboards to the substructure using nails, staples or screws has proven its worth and is supported by relevant technical documentation. On solid masonry, fermacell® gypsum fibreboards can also be bonded using fermacell™ adhesive.
Other alternative methods, such as direct bonding to the substructure or substrate using so-called construction adhesives, are certainly possible; however, given the wide variety of products available on the market, James Hardie Europe is unable to make any recommendations or provide any warranty in this regard.
fermacell® fibre gypsum products consist of 80% gypsum – a mixture of natural gypsum and flue gas desulphurisation (FGD) gypsum – and 20% paper fibres, which are obtained from waste paper through a recycling process. These two raw materials are processed into a homogeneous mixture and, after the addition of water – without any further binding agents – are pressed under high pressure into stable boards, dried, treated with a water-repellent agent to make them hydrophobic, and cut to the required sizes.
fermacell® fibre gypsum boards do not contain any substances that are harmful to health.
The absence of adhesives means there are no unpleasant odours. The boards and the manufacturing process have been tested by the Rosenheim Institute for Building Biology with regard to healthy living and environmental protection. Due to the excellent results, the fermacell® fibre gypsum boards have been awarded the ‘Tested and recommended by the IBR’ seal of approval. Furthermore, the ECO certificate confirms that they are free from harmful substances.
Floor
No, that's not possible.
The fermacell® screed elements require a full-surface base that is sufficiently load-bearing, level and dry. A sufficiently dimensioned, non-springy subfloor must therefore be in place on the wooden joists, e.g. made of boards or suitable wood-based panels. If there is limited installation height available for the screed, this subfloor can be laid between the wooden joists.
fermacell® flooring elements are made from the same fibre gypsum boards that are used on walls and ceilings. It would therefore, in theory, be possible to use them.
In practical terms, there are a number of reasons against this:
Two-layer planking is not always necessary,
the proportion of joints is greater,
the sound insulation of the wall structure is compromised by the bonding of the panels and the resulting rigidity,
From a fire safety perspective, there is no direct evidence,
and last but not least: the price per square metre is higher.
No. The fermacell® Therm25™ element combines a load-distribution layer and underfloor heating in a single system.
The system incorporates a fermacell® gypsum fibreboard, which is glued and screwed or stapled in place as an additional layer above (Option 1) or below (Option 2) the fermacell® Therm25™ elements.
In option 3, fermacell® Therm25™ panels can also be bonded directly to a level, load-bearing substrate without the need for additional fermacell® gypsum fibreboard.
Detailed installation instructions can be found in the document ‘fermacell® Therm25™ Elements – Planning and Installation’.
A variety of resilient floor coverings can be laid over fermacell® flooring elements, such as carpet, laminate, cork, PVC, linoleum, elastomer and LVT design flooring.
As wooden floorboards can continue to dry out and shrink, and there is also a risk of knots falling out, a vapour-permeable underlay must be laid before the levelling compound is applied. In the area of the floorboards, a vapour-permeable underlay should be considered before installing the levelling compound, if necessary. To reduce impact noise, the installation of 30 mm fermacell®® We recommend screed elements containing wood fibre (2 E 31).
There are two different fermacell™ Therm25™ templates:
fermacell™ Therm25™-167 template for use with fermacell® Therm25™ elements with a 167 mm installation spacing
fermacell™ Therm25™-125 template for use with fermacell® Therm25™ elements, 125 mm installation spacing
The fermacell™ Therm25 template is the same size as the fermacell® gypsum fibreboard (1500×1000 mm) and is positioned precisely on the fermacell® Therm25™ elements, in the exact spot where the cover board is to be laid, prior to bonding.
When using fermacell™ Therm adhesive, at least 9 fixing points are required per cover panel (1500 x 1000 mm). To ensure these are evenly distributed, exactly one fixing point should be applied to each grey-shaded area.
(Note: When using fermacell™ screed adhesive, all fixing points on the template must still be used).
If heating pipes are visible in the holes during the inspection of the fields, these must be marked or covered with tape to ensure that no fasteners are attached at these points.
The fermacell™ Therm adhesive or fermacell™ screed adhesive can then be applied, with the fermacell® gypsum fibreboard used as a cover board. The template is placed on the covering board in the same orientation and the covering board is secured with at least 9 (or 59 or 70 in the case of fermacell™ Screed Adhesive) screws/clips.
Each pallet of fermacell® Therm25™ elements comes with a fermacell™ Therm25™ template. This can also be reordered separately if required:
fermacell™ Therm25™-167 Template: 79190
fermacell™ Therm25™-125 template: 79189
Detailed installation instructions can be found in the document: "fermacellTM Therm25™ Underfloor Heating Elements – Planning and Installation". A helpful installation video is also available.
A wide variety of insulation layers can be installed beneath fermacell® flooring elements. For more detailed information, please refer to our flooring installation guide.
Yes. With option 3, fermacell® Therm25™ panels can be bonded directly to a level, load-bearing substrate without the need for additional fermacell® gypsum fibreboard.
The key benefits compared to conventional wet screeds, such as cement screed, self-levelling screed, anhydrite screed, etc., these screed elements offer: short installation times, rapid readiness for use, no construction moisture, low build-up heights and low weight.
No.
The fermacell™ thermal insulation loose-fill is designed for installation beneath fermacell®. The flooring elements are too soft and are therefore unsuitable for this purpose.
Under fermacell flooring elements, only fermacell™ levelling screed and fermacell™ bonded screed have been tested and approved.
fermacell™® Screed elements weigh a maximum of 32 kg/m². This means that the load on the ceiling is minimal. With the honeycomb insulation system, the weight increases by approx. 45 kg/m², which does not require separate structural analysis for timber-beamed ceilings in newer buildings without visible defects or structural damage, as the original structural calculation should have taken into account a live load of 200 kg/m². When modernising older buildings, it is essential to consult a structural engineer.
Please note that the screed honeycomb must always be laid directly onto the subfloor and then filled with fermacell™ honeycomb fill. If a levelling of more than 3 mm is required, this is achieved using fermacell™ levelling fill on top of the honeycomb.
The top surface of the fermacell® flooring elements features printed markings (centred: ‘fermacell® flooring elements’; on the stepped joint: product name, CE marking, barcode, etc.). The elements are laid in the room from left to right.
The material properties of the screed elements are the same on both sides. In principle, therefore, it would not matter which side is on top.
When laying the tiles, simply ensure that the interlocking edges are positioned correctly. The tiles should always be laid on top of one another, never slid underneath!
fermacell™ levelling compound is a specially dried, mineral-based aerated concrete granulate. The angularly crushed granules, which vary in grain size and have a rough surface, interlock when poured and levelled. Due to the grain size, the required stability is only achieved at a minimum layer thickness of 10 mm.
When discussing structures using fermacell® flooring elements, the term 'systems' is very often used.
Unlike wall structures, floor structures are, quite literally, built upon one another. This means that the weakest link in this structure determines the performance of the entire structure. The fermacell® flooring element takes on the load-bearing and load-distribution functions. To ensure this, the substrate (e.g. fill, insulation material) must have a minimum strength. The structures and products shown in our fermacell® installation guides have been tested and guarantee this strength. Of course, due to structural requirements, it may happen that the required structure is not mentioned in the documentation. In such cases, please contact our technical customer hotline:
The maximum screed thickness for fermacell™ levelling compound is 100 mm in application area 1 (private residential use). In all other application areas, it is 60 mm.
Compaction is generally not required. However, the fill height may be dictated by fire safety or sound insulation requirements. Furthermore, the fill height may be limited by the use of large-format tiles. The use of underfloor heating or suitable mineral wool insulation boards on the levelling screed requires a cover board, e.g. a 10 mm fermacell®® fibre gypsum board.
The fermacell™ honeycomb insulation system consists of the fermacell™ screed honeycomb, the fermacell™ honeycomb fill and the fermacell® screed element. The fermacell™ screed honeycomb is a cardboard honeycomb with a closed back, available in thicknesses of 3 or 6 cm, which is filled with the special fermacell™ honeycomb fill.
This honeycomb insulation system, laid directly onto the (unfinished) timber beam ceiling, provides additional weight and, in combination with the floating fermacell® screed element, helps to reduce sound transmission. The sound-insulating effect of this system is significantly enhanced by decoupling the sub-ceiling (e.g. using a spring-mounted suspension system).