No, protection needs to be applied to the underside of the ceiling using an appropriate board such as FERMACELL fixed to the underside of the ceiling constructions. See the details on the ceiling web pages for specific constructions.
No, Fermacell flooring is not a spanning element. The flooring should be laid on a supporting element such as flooring grade chipboard or an existing floor.
Yes - Fermacell flooring is laid as a floating floor - that is to say it is not fixed through to the existing structural floor. It is therefore important that only that the proprietary Fermacell screws and floor glue are used to ensure that the elements are not fixed to the subfloor. 22 mm screws should be used with 25 mm or greater flooring elements to ensure that the flooring is fully floating, and 19 mm screws should be used with 20 mm elements. Fermacell floor glue should be laid in two lines on the supporting seam.
Because the floor floats, it must be isolated from flanking structures (walls, skirtings etc) using perimeter isolation strip.
Minor unevenness (up to 1 mm) can be accommodated by the 30 mm element. Greater variations can be taken up by Fermacell Leveling Compound. Floors that are uneven must be levelled, otherwise the floating floor is not fully supported and the published traffic and point load capabilities are not achieved. This is particularly relevant when laying certain floor coverings (such as Marble) which needs a rigid substrate to prevent cracking.
As long as it of flooring grade and is suitable for use under floating floors, yes. Fermacell thermal flooring elements are currently available in three variants to accommodate different 'U' value requirements. If you have a specific thermal insulation target then select the insulation on this criteria and then lay the Fermacell boards (2E11 or 2E22 depending on point load requirements) over the top as a floating floor.
Whilst Fermacell is a moisture rated board, it is not waterproof and boards with elevated moisture content should be allowed to dry prior to use. Specifically, damp boards cannot be properly jointed, and may be subject to movement as the moisture content changes. We recommend that they are stored flat off the ground in a dry room. Under these conditions, boards should reach a normal moisture content within 48 hours if the temperature is >15 degrees Celsius and relative humidity of the surrounding atmosphere is <70% Rh. If you are in doubt, the moisture content may be measured by using a moisture meter, and must be no more than 1.3%.
The new building regulations which came into force in July 2004 for new build and July 2003 for RMI require not only a greater degree of in situ testing than before, but also the minimum acoustic performance has in many cases been modified to include a traffic correction factor, or Ctr. For this reason, the anticipated performance will depend on the existing floor construction. Fermacell now co-sponsor an informative website which not only gives details about the new regulations and their effect on housing, schools and hospitals, but also includes the latest test data on a variety of floor (and wall) constructions that are designed to conform to the new requirements. To go to this website, please go to: http://www.acousticregs.info
In general, use the woodfibre. The two variants are acoustically very similar, and the woodfibre one has a higher point load capacity. Woodfibre is also ecologically more sound than mineral wool. However, whilst the Fermacell board is moisture tolerant, the woodfibre layer bonded to it's underside is not and if you are installing the flooring elements in an area likely to be affected by moisture (bathrooms and kitchens are typical examples) then select the mineral fibre variant. The two variants are compatible with each other.
With few exceptions, yes. Please refer to the individual flooring guide for procedure, but most floor coverings including laminates, tiles, latex, linoleum, vinyls and carpets may be laid directly onto Fermacell flooring without any additional preparation. Care should be taken to ensure that both the (Fermacell) flooring overlay and any other finishes are fully acclimatised prior to installation. Parquet flooring may be laid directly as long as it is in herringbone format, but special precautions should be taken when laying solid timber flooring because of the tendency of the timber to change dimensionally with variations in temperature and humidity.
Because Fermacell is relatively inert, timber mechanically fixed to the board may set up a 'bi-metallic' effect resulting in distortion. For this reason, solid timber floors should be laid either as secondary floating floors; or fixed to counter battens which are in turn fixed to the Fermacell board, or laid using a resilient adhesive system with a slip layer. One such syste
In general, the floor will be ready to accept floor coverings as soon as the floor glue has dried out and the screw or staple heads have been stopped with Fermacell filler. Also, ensure that the room is fully acclimatised prior to applying any finishes.
Tiles should be laid using a thin bed method and with a fixing adhesive with a low water content. This is because the Fermacell flooring can absorb water from the grout and temporarily lose some strength. Uneven tiles often require thick(er) bed methods with a consequent increase in the water load on the flooring. In these cases the Fermacell should be sealed with a waterproof PVA or similar prior to tiling to inhibit water absorption. All tiles should be properly spaced (to avoid capillary action) and left ungrouted until the fixing adhesive is fully dry.
Fermacell flooring is suitable for use with warm water systems laid in tracked insulation, with a maximum pipe temperature of 45° C. Electrical systems or hot water systems are not suitable for use with Fermacell elements.
By using genuine Fermacell flooring screws. For the Underfloor Heating variant (25mm thick 2E22), 22mm Fermacell screws should be used. See the product pages for all details of Fermacell boards and accessories.
Fermacell flooring guarantees high point load capabilities and may be used with a wide variety of floor coverings and in both domestic and heavy commercial applications. We have tested many of these applications and whilst the thinner 2E11 system may be suitable for light/domestic applications, it is not as rigid as the 2E22 system. For this reason we always recommend the latter unless there is a particular combination of UFH manufacturer's system and floor covering that has been jointly tested and a certificate issued. The current list of manufacturers with (Xella) certified systems is available from our Hotline - +44 (0) 870 6090306.
In particular, lighter grades of Polystyrene will flex under heavier point loads. Systems on suspended timber joist floors need a more rigid overlay, and at the edge of the room, many UFH systems have multiple tracks to accommodate variations in pipe returns which in turn requires a board with greater spanning ability over these voids. If, for any of these reasons, there is a tendency for the floor construction to flex, a rigid but weaker floor covering - for example marble tiles - may crack.
It is also possible to extend the point load and traffic/application range by adding a third layer of Fermacell wallboard - please see the Fermacell Flooring Instruction Manual for more details.
Please refer to the heating manufacturer's detailed instructions. Most manufacturers will require the heating to be slowly brought up to temperature over a number of days. The heating should not be turned on until the flooring glue has fully dried (typically 24 hours). All floor coverings should be applied only after the heating has been tested.
