Welsh Slate is the lucid choice for Lucent.


A project that exemplifies a “perfect application of Welsh Slate to unify a unique roofscape,” has drawn to completion by Wates on a landmark site in London’s iconic West End.

Prior to its development, the triangular site at Piccadilly Circus was a mixture of 13 buildings of different ages, architectural styles, listings, ownerships and uses. But they are now brought together under a new Welsh Slate roof that in itself mimics the complex labyrinth below.

Fletcher Priest architects’ 144,000ft2 mixed-use scheme for Landsec’s Lucent, the new name for the city block that accommodates the Piccadilly Circus Lights, has been radical, involving rebuilding brick by brick and then vertically stretching some of the facades, creating pocket balconies and a three-storey basement, and tucking 20 south-facing rooftop terraces into the Welsh Slate roof that was deliberately facetted to preserve protected views.

To meet their ambitions, a mix of Welsh Slate’s County-grade 500mm x 300mm and 500mm x 250mm Cwt-y-Bugail Dark Blue Grey slates were laid over 1,750m2 on pitches ranging from 20° to 80° by EJ Roberts Roofing Contractors.

The almost vertical slating features on the Lucent entrance in a narrow frontage to a new infill building. It is one of the few areas of the now seven-storey elevations where the geometry of the new city block-sized roof is visible, another being on a replacement retail unit.

The structure of the roof covering the commercial/office, retail and residential elements of the scheme comprised a steel frame with insulated cassettes that were craned into position and then covered in underlay and counter battened ready for the Welsh slates to be nailed into position.

Project architect Joe Sweeney said: “It was a contextual decision to use Welsh Slate as it is appropriate for the building and the area. The roof is a very important part of the project as it unifies the 13 different buildings into one consolidated project.

“It was important to us to use local and traditional products and their sustainability was equally as important, so the Welsh Slate met all those requirements.”


Paschal Fennelly, estimator with EJ Roberts, who were 12 months on site, said: “The original design for the roof was a high-tech luminous curtain roof screen but the planners and conservation officers stepped in to insist that all new pitched roofs were done in new Welsh Slate as some of the retained sections of the building and facades had listed status.


“The Lucent building is right on top of Piccadilly Circus which presented many logistical challenges. It is estimated that more than 100 million people visit Piccadilly Circus every year. On average, this means 8.3 million people every month, and two million people every week. You can imagine that trying to build in that ultra-busy environment is very challenging.

“Whilst we had no curved roofs, we certainly had plenty of multi-faceted roof slopes. We used zinc capping and valley details to weather the junctions, strengthened by galvanised steel lining sections. The same application of zinc with the galvanised steel was used for all weathering details relating to the new Welsh Slate roof.”

Paschal added: “It was one of the most challenging contracts ever for our company, in terms of restrictions on traffic and parking, waiting times for the crane to get the materials to the roof, controlling the loading zones, staying safe, protecting the public, controlling the hoisting activities, working at height, the risk management of Health and Safety requirements, quality management systems – all that takes up so much energy and management time.

“But this roof is probably a perfect application of Welsh Slate to unify a unique roofscape – an excellent roof design and a new Welsh Slate with top-class roofers equals a great roof.

“I would like to say that the real key to the success of this project is down to our directors Emerson Bennett and Dean Skipper, aided by our site surveyor James Wallace. They worked hard to drive this job and deliver it on time and on budget. We are also blessed to have great roofers who delivered the best standards of workmanship, and of course, the star of the show is the new Welsh Slate.”


Fletcher Priest’s project book says of the roofscape algorithm: “The algorithm for the design of the roof is generated by the pedestrian experience of walking around the building. Anyone standing on the opposite pavement of the surrounding streets should not be aware of any of the roof penetrating the skyline when looking up at the eaves. This results in an unusual but functional roof geometry, with the lowest angles generated becoming terraces.

“There are planning constraints around the viewing corridor to Westminster Palace from Primrose Hill, which is a statutory view needing to be maintained. Even though there have been viewing breaches [by others], the building at Piccadilly Circus does not exceed the permitted height limits.

“Conceptually, the roof is the key unifying element of the whole building, bringing together its diverse facades and levels, and touching down towards the ground with a flourish at the former Rainbow Corner and Sherwood Street entrance.

“The design may be an exercise in how to hide the roof from the street but it would be photographed or filmed from above, so the roof’s sculptural quality is important. When seen from above, the roof becomes the fifth elevation. Piccadilly Circus has to be one of the most popular locations in the UK for aerial shots for use in movies, video game, advertising and print publications.”

And of the 3D slate roof, it says: “The slate roof design fits within the context of historic Westminster, as does the inclusion of traditional mansard roofs. Working through the various facets of the roof with the structural engineers required 3D modelling to turn sometimes irrational shapes generated by the street-view algorithm into buildable forms.

The roof has been designed using modular systems – cassettes which are manufactured offsite then dropped into place on the building, with roof slates subsequently applied. Charlie Scott, the structural engineer, described it as a modern way of designing a tiled roof, as the geometry requires interesting structural design, and he doubts if it could have been done without BIM. The process is much simpler with a 3D virtual model, as it’s possible to test every awkward interface and precisely set out the steelwork underneath.

“Alongside the modern construction techniques for the triangulated and faceted roof structures made offsite, the mansard roofs above the historic facades are built on-site using timber – an environmentally sustainable material for roof making. Warren Alexander-Pye [project director at Landsec] describes using a traditional roof material like slate on geometrically challenging roof shapes, and then having to squeeze gutters and drainpipes into the gaps. He describes the result as super-sharp, giving the building an identity when seen up above.”








SFS UK, the world’s largest manufacturer and distributor of carbon and stainless-steel fastening solutions for roofing, cladding and façade systems, has been offering support and advice to specifiers within the construction industry for more than 120 years. Today, this support includes a series of informative podcasts.


There is a series of three podcasts focusing on fall protection and subframes, each lasting around 30 minutes, discussing fragile roof design trends, the effects of thicker insulation in rainscreen cladding subframe systems and the effect of rainscreen subframe systems on the overall performance of external walls.  The podcasts address industry regulations and best practice in installation; they are designed for everyone in the construction industry.


Also on offer is SFS PocketTalks, a range of shorter podcast episodes addressing the latest construction practices.


With four episodes in the series at around five minutes each, PocketTalks discuss u-values, the challenges created by a lack of testing standards for permanently attached fall systems, the implications of the UK Cabinet Office’s Construction Playbook and consider the impact of thermal bridging on rainscreen subframes.






For further information, call 0330 0555888 or CLICK HERE TO VISIT THE WEBSITE  




Metal building envelope specialist SIG Building Solutions has launched a warranted twin skin system called ‘Gemello’.

Gemello, is a self-supporting roof and wall system consisting of a trapezoidal pre-finished steel liner and outer sheet with a Class A1 non-combustible glass fibre insulation in between.  Under development for a number of years, the system is now available for the roofing and cladding of steel framed buildings, including industrial, retail, office, health, education, and leisure buildings.

This new SIG Building Solutions roof and wall system can be tailored to suit the aesthetic, acoustic, thermal, fire and loading requirements of a building.  The Gemello external profiles are available in an extensive range of colours, profiles and coatings, enabling designers to create visually-engaging buildings.

In addition, the Gemello system can provide U-values down to 0.12 W/m²K or lower depending on the required performance. The design of a twin skin system also allows for denser materials to be used in its construction, improving acoustic sound reduction and rain noise.

A key feature is the Gemello system warranty.  The Gemello warranty is flexible, providing warranty periods for 12, 25 or 30 years. This warranty covers all the components within the twin skin system and the system itself.

SIG Building Solutions provides an extensive range of accessories for Gemello, including rooflights, gutters, flashings, fascias and cappings.

Working alongside the customer with a collaborative approach, SIG Building Solutions provides the technical expertise and robust product offering to develop a bespoke, effective roof and/or wall system with minimum complexity.

Commenting on Gemello, Samantha Jones, SIG Building Solutions’ commercial development director, said,


“An exciting product development, Gemello is an example of the innovation and expertise that is made available by bringing our extensive manufacturing experience together in one dynamic built up system offer.”

SIG Building Solutions


Following more than a decade of operating collaboratively alongside each other, SIG’s team of cladding and sheeting manufacturers came together in Q4 of 2022 to provide a cohesive customer facing brand under the SIG Building Solutions banner.

Providing complementary product ranges and servicing regional markets to create a national solution, these manufacturing businesses are prevalent in the agricultural and light industrial sectors and are well placed to combine their resources to present their service to a wider audience.


“SIG Building Solutions provides a relationship-driven, solutions-focused, single point of contact which translates well across the industrial, commercial and agricultural build sectors.  Our manufacturing businesses combine decades of roof and wall system expertise and manufacturing know-how which have been brought together and backed by the robust supply chain and extensive capabilities of SIG plc,” said Sam Jones.


SIG Building Solutions manufactures secondary steelwork, insulated panels, single and twin skin roof and wall profiles, bespoke fabrications, rainwater goods and ancillary products.

In addition, SIG Building Solutions has developed a range of solar car park canopy structures, and works alongside solar system providers to help organisations with large parking facilities generate solar energy and reduce their carbon footprint.






Cembrit is delighted that its Moorland fibre cement slates have been specified and installed at the new campus development at the University of Northampton. Situated on the River Nene the new Waterside Campus features a mixture of academic buildings and student accommodation. Specified by Stride Treglown and installed by Russell Roofing, the Moorland slates dressed edge provides an aesthetically pleasing natural looking roof covering, for the new prestigious student accommodation blocks at the university, at a lower installed cost than natural slate.

Located on a former brownfield site, the development responds to the industrial heritage of the site in a contemporary way. The student residences are located immediately adjacent to the new academic accommodation and incorporate a variety of additional facilities including a health centre, multi-faith chaplaincy, convenience store, bank, hotel school and launderette. The additional facilities within the development take a holistic approach to urban regeneration as well as giving the university an opportunity to consolidate its campus estate into one location. The new student residences, which are being developed in two phases, consist of a mixture of shared townhouse and cluster flat accommodation with the Moorland slates being installed on pitched roof areas including the main roof and mansard sections.

Keystone Roofing have supplied Russell Roofing with over 47,000m² Moorland slates so far and Frazer Simpson, Director of Russell Roofing is delighted with how the project is taking shape: “The development is a great looking project and looks particularly impressive with its waterfront location. The Moorland slates fit in perfectly with the surrounding and with their dressed edge and lightweight construction add a classy, but easy to install quality to the project. We’ve used them before and definitely will do again.”

Cembrit Moorland slates are designed with a dressed edge and smooth surface, they are light weight, pre holed and easy to cut with hand tools making them a cost effective product an added benefit for the University of Northampton. Moorland slates random, dressed edge creates a roof slope with a natural appearance, they are fully coated with a high quality, semi-matt acrylic pigmented finish which ensures the natural appearance is visible from street level.

For further information visit, email or tel: +44 (0) 208 320 1184.

Cembrit Glendyne natural slates have been specified and installed on a unique renovation project for the Historic Hampshire landmark, Netley Chapel, which saw the local community contributing financially to the restoration project. Before slating began, the public were invited to site to mark the occasion and “sponsor a slate”. For a small donation, visitors wrote a message and signed the reverse of a roof slate. More than 900 Glendyne slates were decorated, raising £6,600 for the friends of the Royal Victoria Country Park. These slates were then installed on the roof of the chapel by Elliotts Premier Roofing of Southampton.

Royal Victoria Country Park was once the site of the world’s largest military hospital, the Royal Victoria Hospital (or Netley Hospital). Now, all that remains of the original hospital structure, which fell into decline after being severely damaged by fire in 1963, is Netley Chapel. Thanks to a multi-million pound grant from Hampshire County Council and the Heritage Lottery Fund, the Victorian-era building has recently undergone extensive renovation, and now marks the beginning of a new chapter for the chapel.

Hampshire-based construction company, Brymor Construction was appointed as the main contractor for the project alongside roofing subcontractor, Elliotts Premier Roofing. Having worked with Cembrit many times in the past, Elliotts Premier Roofing selected 610mm x 305mm blue-grey Cembrit Glendyne natural slates for the refurbishment of the roof covering: “As one of the oldest companies in Southampton, it’s been a privilege for us to have played such a pivotal role in this project and work with other local organisations to restore this iconic chapel,” says David Stubbington of Elliotts Premier Roofing. “We chose Cembrit Glendyne slates for the project due to its flexibility to accommodate the roof design of the prestigious building. The end result is impressive and Glendyne really accentuates the character of the chapel.”

The chapel re-opened to the public in summer 2018. An exhibition in the main body of the chapel tells the story of the former hospital, from its beginnings in the 1850s, through the Boer War, and both World Wars up to the present day.

The project was completed in a timely fashion, and is one of the first to utilise the new large 24″ x 12″ (imperial) format. Netley Chapel was finished to an extremely high standard. Cembrit was on hand to offer support and advice for this landmark renovation project. “I assisted Hampshire Council with writing the roofing specification for this project,” commented Phil Wilden, Technical Manager Pitched & Small Element Roofing Products at Cembrit. “Throughout the roof construction phase, our Regional Sales Manager and I made routine visits to the site to ensure the product was being installed to the requirements of the specification and that of British Standard BS5534. This highlights the level of technical support that we offer our customers.”

Glendyne is a high quality slate that combines first-class performance with all the inherent beauty of natural slate, making it the ideal ‘natural’ choice for specifiers and roofers. Available exclusively from Cembrit in the UK, Glendyne is a distinctive blue-grey colour. The Glendyne quarry is one of the most modern slate quarries in the world. The quarry operates a quality management system based on EN ISO 9001 which is externally audited. This standard is adhered to rigidly, as are all quality standard procedures required by each regional market the quarry supplies.

Glendyne is tested to BS EN European standard, BS EN 12326-1:2014 which requires many of the laboratory tests (‘type testing’) to be performed at least annually and the factory production control (FPC) performed and recorded as a matter of routine by the producer.

To watch a video on the project, visit

For further information visit, email or tel: +44 (0) 208 320 1184.

The Triangle, Cambridge Assessment’s new international headquarters, brings together all the company’s Cambridge-based staff under one Alumasc-protected roof.

Designed by HLM/Sidell Gibson Architects, all flat roof areas utilise Alumasc Roofing Systems’ Hydrotech Hot Melt and Alumasc XPS insulation, offering a total system solution. All upper main roof areas drain onto 3 x single storey podiums that have the patented, single source Alumasc BluRoof Drainage System, along with Blackdown Green Roof to provide a habitable space for people to enjoy.

Alumasc’s BluRoof system reduces and controls the peak rate of storm water discharge from roof areas. Detention of storm water up to a prescribed maximum hydraulic head occurs, with subsequent discharge controlled over an elongated time period.

The BluRoof drainage strategies were introduced at design stage to help meet SuDS (Sustainable Drainage Systems) requirements, and Alumasc worked extensively with Capita to achieve the required reduction in rainwater run-off.

Wayne Farrington from Cambridge Flat Roofing, the Alumasc-registered approved contractor which carried out the installation, acting as sub-contractor to Bouygues UK, said “This has been an excellent contract to be involved in, one of our first major BluRoof projects. The level of service and input from Alumasc’s Technical department, both internally and on-site, along with Alumasc’s Customer Services team, have been outstanding.

“Combined with the Hydrotech BluRoof Structural Waterproofing system, a system we have significant trust and experience in installing, we feel we’ve delivered a project we can be proud of. The feedback we’ve received from our client has been extremely positive and we look forward to our next Alumasc BluRoof.”

For further product information about Alumasc’s BluRoof Drainage System click here or call our technical team on 03335 771 500.
Further details about Alumasc’s full range of waterproofing systems can be found at or call the Alumasc technical team on 03335 771 500.

Easy to install Cembrit Moorland Blue/Black slates have been used on phase two of St Modwen’s new build housing development in Dursley, Gloucestershire. Chosen for their attractive appearance, and following a successful phase one, the Moorlands were once again supplied by Willis Westcott and installed by Mcdonnell-Price, a local roofing contractor.

The properties at Littlecombe have been built using a blend of modern and traditional materials which gives the development a timeless appeal. The Moorland Blue/Black slates provide a contrast with the light coloured fascia materials and surrounding greenery. This clean appearance is enhanced by the first class installation work carried out by McDonnell-Price across the development, which features roofs with Velux windows and many vents and valleys, alongside several pitch variants of between 30 and 45 degrees. Brandon McDonnell, of McDonnell-Price is very satisfied with the end result:

“I’m pleased with the way the project came together – everything just seemed to click into place. We like Cembrit’s Moorland slates and with a project like this, one that involves a lot of detail, it was good to have a slate that is lightweight, as well as easy to cut and fix. I also like the way dark Blue/Black colour stands out and nicely defines the roof lines against the surroundings.”

Moorland 600×300 slates were supplied by Willis Westcott, a large roofing supplies merchant in the region, as well as ‘doubles’ for the verges. The slates are fixed with two copper nails at the top of each slate with a copper rivet supporting the bottom of each slate. Moorland slates have an appearance close to that of natural slate. Their smooth surface and authentic dressed edges lend themselves to all manner of prestigious applications. They are manufactured to the highest European standards and are lightweight, pre-holed, suitable for all types of projects, easy to handle and install, durable and an economic alternative to natural roofing materials.

Moorland slates are manufactured using Portland cement together with a non-asbestos formulation of superior blended synthetic and cellulose fibres. Moorland slates are pigmented during production and are fully compressed. They are finished with a high quality, semi-matt acrylic coloured coating to the top face and edges and a tinted, high performance binder to the back face.

For further information visit, email or tel: +44 0208 320 1184.

(Photo caption: the recently completed new Alchemist bar and restaurant at Salford Quays, which features a striking golden building envelope installed by Longworth, created using fastening systems by SFS. Courtesy of Artez / James Andrews.)

Global group sales growth of 13.7% in 2017 for fastening systems manufacturer SFS, reflects the growing customer demand here in the UK for high performance fixing solutions for the building envelope, which the company is set to support further with its unveiling of the industry’s first complete package for rainscreen systems.

In addition to an expanded range of SFS-branded products and services being readied for launch in 2018, the company now offers Nvelope rainscreen support systems after the manufacturer joined the SFS family in 2016. This enables SFS to provide high performance Nvelope bracket and rail systems for rainscreen cladding and SFS-branded fasteners as one package, offering important warranty benefits and a simplified supply chain.

An extension to this package is also available to customers seeking to incorporate a working at height safety system as part of their envelope project. This is provided by SFS with its industry-leading Soter Safety Systems solutions, giving specifiers and contractors the assurance that key elements of the building envelope’s construction and installation are provided by a market-leader renowned for its technical excellence.

Across the globe, SFS provides fastening solutions in a diverse range of industries, including medical equipment, automotive, electronics and industrial. In the UK, SFS is synonymous with high performance fasteners for roofing and cladding, as well as other structural applications, and its range of precision-engineered door hinges. Over the last 12 months, its organic sales have grown strongly by 7.4%, to achieve overall sales of around £1.24bn (CHF 1.633bn Swiss Francs).

David Wigglesworth, UK Managing Director of SFS, said: “The SFS brand stands for quality and engineering excellence, so our customers can be confident that every solution we provide meets the highest expectations. Nvelope and Soter Safety System are, therefore, perfect additions to the SFS family as architects seek greater certainty on building envelope quality and performance, and installers look to solutions that help them work quicker, more profitably and safer.

“With our new family of systems, SFS is unique in the market in providing a complete solution that is underpinned by quality and reliability. Customers of SFS fasteners have long benefited from the extended life of our superior A4 stainless steel fasteners, often with powder coated colour finishes for outstanding visual appeal, and our innovative flat roofing systems, but they can now access so much more for projects incorporating rainscreen and where a reliable safety system is required.”

Superior quality products backed by expert technical support has been at the core of SFS’s success in serving the building envelope market for more than 30 years with a wide range of solutions for pitched roof, façade and flat roof construction. The company is part of the SFS Group which has annual sales in excess of £1.1bn and a history dating back to the 1950s serving customers in the construction, automotive, electronics, industrial and medical products markets.

Find out more about SFS at

Eight years after being put on the ‘At Risk’ register by English Heritage, the landmark Terry’s Chocolate Factory has a new lease of life, following extensive refurbishment. The 1926, Grade II listed building now starts a new chapter as a care village owned by Springfield Healthcare.

Once home to famous brands such as Chocolate Orange, the factory and offices were closed in 2005 and fell into disrepair over the subsequent decade. Eventually the building, which is part of a 27-acre site, was acquired by Henry Boot Developments for conversion. The renovations included a full roof refurbishment that was undertaken by Hull-based roofing contractor L.A. Hall using a Sika Sarnafil single ply system.

One of the key focuses of the work was to preserve and retain the art deco features of the building while increasing its lifespan. A vital element of the repairs was the work on the existing flat and slate roof areas that were in a very poor state, and a roof for the new additional floor of the building.

Principal contractor Simpson (York) Ltd., brought L.A. Hall on board to complete the roofing works, which comprised a number of disciplines, including heritage Westmorland slating, single ply, zinc cladding and leadwork.

L.A. Hall suggested using a Sika Sarnafil system for the flat roof areas, as it matched the client’s requirements for longevity and sustainability, and is the company’s preferred membrane choice. The project’s conservation officer was initially concerned that the system would be too shiny, but Sika Sarnafil provided a number of samples, and after discussions, the specification was welcomed by all parties.

The project was complex due to the multiple roof areas and detailing. To begin, the existing slating on the central north light roof slopes, which were remaining in place as part of the new scheme, were re-covered using a fully adhered Sika Sarnafil system including G410-EL membrane in Lead Grey.

In addition to the existing roof areas, an extra floor to the building was constructed around the north lights. Its steep slated mansard-type external elevation included approximately 60 dormer windows, which required zinc on all the vertical faces and Sarnafil on the tops. The flat roof area of the extension was then also covered in the Sarnafil system, along with 140m of parapet guttering detailing, and a new roof terrace area.

Nigel Drysdale, Technical Advisor at Sika Sarnafil said “We had a great number of details to consider in order to preserve the original look of the building. For example, the architect and conservation officer required a timber mop roll detail to the perimeter of the main roof and the dormers. So all the parties worked closely to achieve a practical and aesthetic solution, which involved creating detailed life-sized models of key elements. This collaborative and applied approach gave the conservation officer confidence that the detailing was sympathetic to the building’s heritage and that’s what we eventually installed.”

The L.A. Hall team overcame various challenges, including working on sloped areas, tight time scales and challenging winter weather, but thanks to the skill of the fitters and the flexibility of the Sarnafil system, the project was finished to an impeccable standard and on time.

All members on the team agree that the newly refurbished roof looks stunning and will defend this iconic building from the elements for many years to come.

For more information please call 01707 394444, or visit

Cembrit, the leading roofing and cladding specialist is proud to announce the addition of two new sizes to its Glendyne range of natural slates, 60×30 and 50×30, offering roofers larger slates and more versatility when working on lower pitched roofs.

On a roof with a lower pitch, the large size of the slates will not let water sit between the slates and prevents the water from getting through. Larger slates work well on low pitched roofs and are best suited for use in coastal areas where the environment has a greater degree of moisture content.

The larger sized Glendyne natural slates, 60×30 and 50×30, can be pitched at a minimum of 25° and 20° in moderate exposure zones and 30° and 22.5° in sever exposure zones respectively. The slates exceed the common 2:1 length width ratio, allowing for specification on greater range of roof pitches. The range offers a quality alternative to Welsh Slate and is readily available. Cembrit also has the facility to examine individual cases and offer specific advice on minimum pitch per project outside the parameters of BS 5534.

Glendyne is a high quality slate that combines first-class performance with all the inherent beauty of natural slate, making it the ideal ‘natural’ choice for specifiers and roofers. Available exclusively from Cembrit in the UK, Glendyne is a distinctive blue-grey colour. The Glendyne quarry is one of the most modern slate quarries in the world. The quarry operates a quality management system based on EN ISO 9001 which is externally audited. This standard is adhered to rigidly, as are all quality standard procedures required by each regional market the quarry supplies. Glendyne, like all natural slate from Cembrit, is tested to BS EN European standard, BS EN 12326-1:2014 which requires many of the laboratory tests (‘type testing’) to be performed at least annually and the factory production control (FPC) performed and recorded as a matter of routine by the producer.

For further information visit, email or tel: +44 (0) 208 320 1184.