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The reconstruction of a rambling old farmyard close to Ely in East Cambridgeshire is making use of well proven Marmox Thermoblocks, specified in three widths as the ideal solution for tackling thermal-bridging around the building perimeter as part of a well-insulated design. Mitchell’s Barn is replacing a sprawling complex of dilapidated tin cowsheds and a rather more attractive oak barn which was founded on a plinth of Tudor era bricks.


Construction site with a concrete foundation, a lone tree, and vehicles. Worker stands near building blocks. Overcast sky and open field.

The original planning permission allowed for the reconstruction of the latter structure, but when the owner, Ben Hughes came to dismantle the outer envelope, much of the timber was found to be rotten while the bricks showed significant frost-damage. The work which got under way earlier in the autumn, is therefore seeing both 215mm and 140mm wide Thermoblocks being used to support a 800mm high brick base which will then carry the conserved oak beams, creating a traditional looking inner ambience.


Ben Hughes commented: “I have taken responsibility for the design as well as the construction of what will be a four-bedroom, three-bathroom property, as a self-build project with the help of a builder, Peter Axton who I have worked with on previous projects. As it is such an exposed site, the house takes the form of a three-sided courtyard which will shelter the south facing terrace. Primarily a Class Q conversion of an agricultural building into a residential building, the new structure is all single storey, but with a mezzanine to accommodate the plant and services that will include an air source heat pump and MVHR system."


"Essentially, we are rebuilding it at the same scale using the same traditional techniques as the original, with additional oak for the frame coming from a tree felled on the site. In order to meet Building Regulations, we have gone for an insulated cavity wall with 150m of PIR insulation for the floor and roof, but when I was researching how to address the issue of thermal bridging at the floor wall junction, Marmox Thermoblock seemed to be the only targeted product solution. In terms of the loadings and the insulation values I am certain it will work well. It’s a good mix of old and new technologies and I’m very happy with the design overall.”


In total Ben and his bricklayer have used 144 x 140x65mm blocks plus 18 x 100x65mm blocks and 50 x 215x65mm blocks, purchased from Insulation Shop on-line. Bedded in conventional mortar, the stepped overlaps between adjacent Thermoblocks have been secured using a high performance (Sika) adhesive.


Ben concluded saying: “The work is progressing well and my bricklayer, Danny, has had no issues with laying the Thermoblocks or cutting them where it has been necessary. Some of the packages, such as for the windows, are still to be placed, but I am confident of the finished property exceeding the current Building Regulation requirements and making a very comfortable home.” 


He is also consulting with Marmox’s technical department over the use of the company’s even longer established Multiboard thermal tilebacker board and other products for fitting out the bathrooms, including at least one wetroom. With a proven track record going back more than a decade, Thermoblocks are available in widths of 100, 140 and 215mm and feature a unique design where two rows of high strength epoxy concrete mini-columns are encapsulated in sections of XPS (Extruded polystyrene).


They are attached at either end to the top and bottom layers of glass-fibre reinforced polymer concrete to achieve a strong bond with the rest of the structure. As well as being used in basement construction and around the floor-wall junction – supporting timber frame as well as masonry walls – Thermoblocks regularly feature at first floor level and beneath parapet walls. They are further employed for swimming pool construction. www.marmox.co.uk

A recently completed contract for an underfloor heating company has demonstrated how a Grade I listed landmark building can undergo a transformation, in terms of its energy efficiency, without any traces being left on the existing historic internal fabric: while also future-proofing it for a switch to a fully renewable heating source in the coming years. 


St. Paul’s Church in Covent Garden is not only known for its architecture - prominent from the famous Piazza - but also as the ‘Actors’ Church’, hosting memorials to film and stage stars from Charlie Chaplin to Sir Noel Coward.  Working with the Diocese of London and under the Church of England Net Zero Carbon programme the Church has achieved what might have seemed impossible less than a year ago. Established in 2024, Ultra-Fin UK Ltd. already has a strong presence in the heritage sector and was exhibiting at this year’s Listed Property Owner’s Club show at Olympia.


Floor heating installation with black and silver panels on insulation. Tools and materials on the floor. Indoor setting, neutral tones.

The team met Westminster Churches Net Zero Forum Officer, Alison Moulden, who made the introduction to the Parish priest, Revd. Simon Grigg, and Parish Administrator, Phil Hunt, who took a keen interest in the potential of the underfloor heating system which is designed for joisted floors.  


Director Tom Dixon-Smith explains the contractual relationship on the project, saying: “Our business model normally involves supply and training but the nature of this project inspired us to take on the role of manufacturer, supplier and installer, using our own team of engineers.  The Church is so important we weren’t prepared to let anyone else complete the project”. 


Tom went on to say “Phil Hunt did a fantastic job of steering the project application through all the Grade I listing and other compliance issues and we supported that by producing what became a 250-page document detailing not just the system but also the installation method.  For example, we had to calculate how many notches we would have to take out of the existing joists once the historic floorboards were lifted and also specify the insulation solution over which the system would run.”


All buildings lose heat through the ground floor and St. Paul’s Church is no exception. Tom explained “we specify insulation beneath our pipework to avoid downward heat losses. In this case the 50mm of fully non-combustible Rockwool insulation maximises the heat from our system whilst making the Church building more energy efficient through restricting building heat loss."


The support for the insulation is provided by a super tough, A1 fire rated breathable PhotonWrap barrier, which also enhances the heat delivery from the Ultra-Fin diffusers by being heat reflective. The membrane was lapped over the joists, held in place with staples and painted black along the top of where it sits on the joists to prevent a shiny glare from between the floorboards. The composite PEX Aluminium pipe and the Ultrafins were installed during a thirteen-day period in mid-August 2025, before the Company’s engineers completed the connections to the existing boiler and undertook the commissioning. The new underfloor heating extends across the whole of the nave from in front of the Altar to the main entrance, leaving the chancel/choir’s flagstone flooring in place. 


The joisted floors cover 2,900 sq.m in 10 bays and they are split into a dozen separate heating zones, prioritising the coldest space towards the Altar, while the pair of eight-port Ultra-Fin Cross manifolds retain spare connections to facilitate the replacement of the boiler with air source heat pumps in the future.  There are hard-wired sensors to ensure the flooring will not rise above 270 C degrees to safeguard the timber. Having overseen much of the work, the Parish Administrator for St. Paul’s,


Phil Hunt observed: “The nave of the Church was previously heated by five radiators which took a long time to heat up (even though we were running the boiler at 80o C). We will be carrying out monitoring, but anecdotally, the times we have turned on the heating it has warmed up far quicker, even though the boiler is running at just 45o C.  The Ultra-Fin system was also ideal for the project because it proved to cause far less harm to the fabric of the building than the alternatives being considered – not requiring the floor height to be built up or screeded, while it remains demountable and – valuably – it was also significantly cheaper than the other systems which would have required far more work.”        www.ultra-fin.co.uk 

Grespania continues to redefine architectural surfaces with ultra-thin, large-format porcelain tiles that are suitable for both interior and exterior spaces, blending beautiful design with an eco-conscious approach. Designed for contemporary architecture and interior design, Coverlam represents the evolution of porcelain: lighter, stronger, and engineered with respect for the planet.


Modern patio with a lounge chair by a pool, leading to an open living room with dining set. Gray walls, wooden pergola casting shadows.

Large-format technical stone represents the next evolution in architectural surfaces - an engineered material created from a precise blend of natural minerals and advanced compounds. Compacting under 30,000 tons of pressure and firing at over 1,200 °C fuse these components into ultra-dense slabs of exceptional strength and stability. The result is a lightweight, non-porous material that illustrates the natural beauty of stone with the superior performance, and sustainability demanded by future forward architecture and Grespania as a company.


Technical Features include:


  • Durability

  • Stain Resistance

  • UV Resistance

  • Heat Resistance

  • Hygiene

  • Design Versatility

  • Environmentally Friendly


Sustainability For The Future


Coverlam was conceived not only as a technical innovation but as a sustainability statement. Produced using more than 90% natural raw materials, and with a manufacturing process powered by renewable energy and closed-loop water recycling, Coverlam, as a product, clearly demonstrates how innovation can lead to meaningful reductions in environmental impact. Its thickness - at just 3.5 mm or 5.6 mm - means up to three times less raw material is required and significantly lower transport emissions are produced compared to traditional porcelain. 


Modern living room with dark marble accents, a fireplace, gray sofa, and armchairs. Wooden coffee table holds books. Large window shows greenery.

Every square metre of tile reflects reduced energy use, waste and resource extraction - proving that genuine design innovation can go hand in hand with a care for the environment. Grespania’s manufacturing facilities operate under stringent environmental management systems, they provide ceramic solutions that optimise efficiency and comply with the most demanding environmental standard, this is key. The result is a product line that supports LEED, BREEAM, and other sustainable building certifications internationally recognised, giving architects measurable environmental performance data they can trust. 


Facades That Benefit


When used in a ventilated facade system, Coverlam becomes an environmental gain. The ultra-thin slabs, measuring up to 1200 × 3600 mm, form a durable exterior layer that allows air to circulate between the wall and the façade. This natural ventilation reduces thermal bridges, reflects solar radiation and regulates building temperature, cutting energy consumption for both heating and cooling. There is an additional acoustic improvement with noise reduction throughout. 


Modern patio with white armchairs, beige tiles, and a glass-walled building. Steps lead to a shaded dining area. Bright, sunny day.

Even more remarkably, façades finished with the H&C Tiles photocatalytic coating from Grespania actively purify the air. The titanium-dioxide treatment reacts with sunlight to break down nitrogen oxides (NOx) and organic pollutants, effectively transforming building surfaces into self-cleaning, air-purifying membranes. 


According to Grespania’s data, 10,000 m² of treated façade neutralises as much NOx as 740 cars emit daily, equating to the purifying power of nine football pitches of green space. This dual benefit of reduced building energy demand and active air purification—making Coverlam the ideal choice for forward-thinking, sustainable architecture and design.


Technical Excellence


Behind Coverlam’s refined surface aesthetics lies robust engineering. Its porcelain composition achieves water absorption below 0.1%, delivering a high resistance to frost, UV exposure, and pollution. Despite its ultra-thin profile, it offers exceptional flexural strength thanks to its reinforced fibre mesh backing, ensuring durability in both new-build and renovation projects. It is lightweight and easy to install which allows facades and interiors to be transformed without the need for structural reinforcement or demolition, reducing waste and installation time. 


Modern kitchen with marble island, white cabinets, and elegant pendant lights. Green plants add freshness. Bright, airy ambiance.

The material is certified under ETA 24/0747, confirming its performance for exterior facades, cladding, and flooring. The large-format slabs allow seamless coverage and minimal joints, creating a calm, continuous surface that highlights the precision of contemporary architecture. The clever combination of proportion, scale, and natural finish gives designers freedom to explore materiality without compromise.


The Concepts Collections: A Unified Vision


Grespania’s Concepts Collections is inspired by a holistic design philosophy - coordinating surfaces, furniture, and architectural elements through a shared material language. Each collection offers multiple finishes, thicknesses, and applications, ensuring design continuity across all spaces. The Imperium series, for example, reflects the beauty and sophistication of marble with fine veining and a luxurious polish; it is available in formats up to 1600 × 3200 mm for large, uninterrupted flowing expanses. Meanwhile, Coverlam Top extends this concept for kitchens and furniture, offering 10 mm and 12 mm thicknesses for countertops, tables, and bespoke joinery allowing for a coherent design flow. Each tile is designed for ease of handling, the mineable side and weight of each tile enables ease of installation. Perfectly suitable for single-person installation allowing for improved efficiency on-site. This integrated approach allows architects and designers to create interiors and exteriors that continuously flow fluently - stone, metal, or cement effects translated across floors, walls, facades, and furnishings.


Modern hotel lobby with marble walls and floor, a reception desk, and wooden seating. A suitcase stands by a chair. Natural light filters in.

Design But Make It Lighter


Beyond its visual impact and endless design possibilities, Coverlam’s sustainability credentials are tangible. Its thin profile reduces CO₂ emissions from production and transport, while its long lifespan and low maintenance requirements further cut environmental impact over time. The ventilated facade system improves building performance, acoustic insulation and protects structures from weathering. Simultaneously, the self-cleaning surfaces maintain their aesthetic integrity with minimal upkeep - rainwater naturally washes away dirt and surface pollutants. Through balancing technical performance, ecological advances, and design versatility, Coverlam proves that sustainability does not require an aesthetic compromise. It represents a material evolution aligned with the architectural priorities of our time: durability, lightness, and responsibility.


A Material For The Next Generation Of Architecture


As cities grow denser and environmental regulation grows, the materials we specify matter more than ever. Coverlam’s contribution goes beyond form and function - it plays an active role in the shift toward carbon-conscious design. Each facade or interior finished in Coverlam becomes part of an architectural ecosystem that generates less waste, consumes less energy, and even cleans the air we breathe. Whether creating a serene interior or shaping a landmark facade, Coverlam stands as proof that the future of architecture lies not only in what we build, but in how we build it.


For further information, imagery, or technical data, please contact: Grespania UK | architects@grespania.co.uk |  | +44 0121 457 6900  |  www.grespania.com/en

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