Cellecta ScreedBoard 20, 28 & 30

We often get asked the main differences between the three different types of ScreedBoard® that Cellecta manufacture, is it just the thickness - 20, 28 & 30?

The short answer is no, there is more to it than that. Here we will explore the applications and solutions that the different types of ScreedBoard® should be specified in to help you select the most appropriate one for your project.

It would be prudent to start with ScreedBoard® 20, as this is the base board for all the versions Cellecta manufacture. A 20mm thick, high density overlay board that is manufactured out of 100% recycled gypsum and cellulose.

The board has exceptional levels of density, a low thermal resistance, and exceedingly low levels of natural movement. This makes it an ideal overlay board for underfloor heating systems, allowing heat from the UFH pipes to pass through the board, ensuring a more responsive system when compared to screed or chipboard/ply overlays.

With Future Homes Standards and current Part L putting an emphasis on low flow temperatures and encouraging heating systems to move towards more carbon friendly sources of heating, such as ground source heat pumps.

Utilising ScreedBoard® 20 over a routed insulation (Cellecta’s Mojave System) will offer excellent heat outputs and comfort at flow temperatures lower than the maximum 55°C detailed in the Part L uplift.

Although Part B stipulates that Fire Separation in dwellings is typically done from the underside to ensure protection of the structural elements, it is becoming increasingly popular to look at other areas of floor designs to increase fire performance. ScreedBoard® 20 has been tested for its fire classification and achieves an A1 – non-combustible rating.

Finally, due to its very minimal thermal expansion (0.015mm/m) no further decoupling layers are required when installing sensitive floor finishes such as tiles, LVT or vinyl. Minimising the labour costs and time when installing these aesthetic floor finishes.

Whilst ScreedBoard® 20 has a high level of mass and density and therefore offers good acoustic properties particularly when it comes to airborne sound. The 20mm board by itself is not enough to meet the requirements outlined in Part E of building regulations. However, when added to a resilient layer this board becomes the natural choice for all types of separating floors, which leads us on to ScreedBoard® 28 & 30.

Both acoustic platform systems incorporate a high-performance resilient layer, FIBREfon 8 or FIBREfon 10, which are fully bonded to the ScreedBoard® 20 on our state-of-the-art production lines, providing two boards to cover a wide range of applications.

FIBREfon 8, is a high-performance fleece that, due to its cell structure and composition will compress more than the FIBREfon 10, therefore absorbing more impact energy imposed on the board. In tests we have undertaken this results in an impact improvement of 4dB on both timber and concrete floors.

With timber and steel joists being a lightweight construction, the base performance of the floor can be inconsistent, and we like to only specify systems that will comfortably exceed building regulations, this ensures confidence and consistency in all our systems and products and therefore the additional improvement on these lightweight cassettes is important to the system. Concrete floors have an enhanced base performance meaning the difference between the fleece and wood fibre is not as critical.

Alongside the performance differential on lightweight floors, Cellecta aim to have all our new build products covered by Robust Detail accreditation, again to give confidence in the quality of our products. To comply with FFT4 (floating floor treatment) on RD concrete applications, you need to prove that your product improves a base floor by 17dB – which we have done in an independent UKAS accredited lab, Sound Research Laboratories for both the 28 and 30mm board.

However, to have the proprietary Robust Detail on timber or steel frame, you need to undertake 30 sets of live site tests over at least 4 different sites – each of these tests need to exceed the Robust Detail performance criteria whilst having a mean average of +5dB across all tests. Not only can this take a few years, but it is also a very large investment for a manufacturer. If one single test does not meet the targets detailed by RD, then you must start again.

ScreedBoard® 28 has undertaken this stringent test regime on three different floor types, gaining RD accreditation for timber i- joists (E-FT-5), metal-web joists (E-FT-6), and steel c-section joists (E-FS-3). It is the enhanced performance and consistency of the FIBREfon 8 on these lightweight floors that make it the ideal solution.

Furthermore, Cellecta, as a responsible manufacturer are always looking for ways to make our systems the best on the market. We began to see a shift in build programmes, with drylining being undertaken after the floorboard was installed on concrete buildings, introducing ScreedBoard® 30 and the higher load capability of the product, meant more flexibility on site for the build programme.

There is also the scenario of acoustics in non-domestic applications such as schools or commercial properties, in this situation it may be prevalent to explore ScreedBoard® 30 even on lightweight structures as the loads imposed could be higher than standard domestic loads outlined in EN 1991-1-1. Having the flexibility to assess the acoustic, structural, and fire performance of a project and then having a solution for every scenario is one of Cellecta’s key strengths and our experienced technical team are on hand to help specifiers select the appropriate solution.

Both ScreedBoard® 28 and 30 can also integrate underfloor heating systems. Separating the ScreedBoard® 20 from the FIBREfon 8 or 10 resilient layer and inserting a layer of XFLO with ULTRAplate or XFLO FF, a foil faced routed extruded polystyrene ensures that all the benefits outlined in the opening section of this document are coupled with unrivalled acoustic performance. The key aspect being that the resilient layer is inserted under the UFH pipes, so it does not have an adverse effect on outputs.

Due to a system first approach that Cellecta prides itself on, this is then classed as our Mojave System, the ultimate underfloor heating and acoustic overlay, in which all the components have been independently tested. This offers a wealth of data giving confidence to specifiers, installers, and end users that they are utilising components of the highest quality backed up by full system data.

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