A new award

This month we are absolutely thrilled to announce that Claridge House, our first retrofit project, has just won an award at The Architects Journal Retrofit and Reuse Awards. These awards celebrate excellence in the renewal and repurposing of existing buildings and emphasise the reuse of materials and structure.

Claridge House, part of the Grosvenor Estate, won the Award for Decarbonisation and Net Zero and we could not be more proud to have been the main contractor appointed to complete the project. Francesco Paparo (now the Design Manager at Castellum) was the appointed Project Architect for Stage 5 (construction phase) at the architects, Studio PDP, and he led the client and novated teams. He worked closely with Lee Boileau of Castellum and his team to make sure that all thermal details and services installation issues were resolved in the best way possible and he acknowledged that Lee’s experience was fundamental to the resolution of certain issues on site. He went on to say, “The Castellum team knowledge, attitude and pride to work were the elements that made me join the team.”

On learning that Claridge House had won the award Francesco said, ‘This achievement stands as a testament to Castellum’s expertise, commitment, attention to detail, client-focused approach and pride in their work. It is a powerful combination and one that very few contractors in the market can genuinely claim’.

Lee Boileau, Castellum’s Retro-fit Co-ordinator and Project Director for Claridge House was at the awards with Francesco and was thrilled by this award. Lee has been instrumental within Castellum for ensuring that, as a main contractor operating in super prime London, our company has the credentials, ability and passion to deliver sustainable projects of this calibre.

Claridge House is an icon now for London and every major city and demonstrates how top luxury apartments can be delivered in existing buildings, targeting net zero carbon emissions. This project has paved the way for all ambitious developers aiming to have sustainable luxury projects in their portfolios and the Castellum team have the expertise to make this possible. This work was done in a Conservation Area in Mayfair (with the very strict planning conditions that come with it). Luxury finishes were applied to a high-risk building (higher than 18m and therefore subject to restrictive fire regulations) achieving Net Zero Carbon, requiring specific knowledge to complete thermal efficient details, integrate and install passive and active thermal control systems (MVHR, solar panels, etc).

The architects responsible for designing the scheme are Studio PDP and their approach to upgrading two floors of this poorly performing mid-rise building in the heart of Mayfair’s Conservation Area, was to show how a heritage building could be ‘both protected and future-proofed while occupied’.

Heating that’s ready for extremes

In line with the UKGBC’s framework definition of April 2019 and seeking to achieve Net Zero, the minimalist strategy retained 100 per cent of the structure. Internal partitions in timber studs and fibre gypsum boards were the only additional fabric. Existing office space was converted back to its original residential use – and all while the building remained occupied. The upgrade of the fabric, plus the addition of air source heat pumps and PV panels, meant that the energy use efficiency exceeded the client brief, while the future-proofing allows for further upgrades.

The existing 1920s neo-Georgian building featured painted timber vertical sash windows to the principal elevations and Crittall windows to the rear and lightwell. Secondary vacuum glazing was added to the former, while the latter were replaced. The judges admired what they said was a clear winner and praised the ambitious efforts. One called the project a ‘best-practice retrofit’ and said the architect ‘had done it all and done it well’. Another described the scheme as ‘surgical’, adding: ‘This is replicable and could be applied multiple times in somewhere like Mayfair.’

This result was possible thanks to the accurate studies and thermal analysis made during Stage 5 which included external wall cavities, window reveals, internal/external wall junctions and wall/ ceiling junctions. Francesco said, “Lee’s expertise was essential as certain solutions were not practicable and new solutions were proposed and adopted. The execution of these details was crucial as a non-correct installation of any of these details on site would have caused a reduction of thermal efficiency, air leak, condensation issues, damp areas, mould formation, etc. Claridge House is an example of collaborative retro-fit knowledge at all levels, from paper to site.”

Preparing for the unexpected

In November 2023, as we were embarking on this fantastic project, we ran an article about retrofit (to read the article click here). If you haven’t read it, it really is worth a read and, almost two years on, we are delighted to have played our part in proving that the challenges that lie ahead for the construction industry can be met. Both Lee and Francesco are incredible assets to a team that our Board Directors are proud to lead. Castellum continues to acknowledge that we all have a responsibility to transform the built environment and we remain committed to combining our luxury residential build experience with expertise in the application of successful retrofit across all our locations and investing in our team to help enable this.

The team celebrating include Castellum, Grosvenor Estate (the client), Studio PDP (the architect), Elliott Wood and Jackson Coles (also part of the client team).

High winds

We’ve gone from high temperatures to high winds this month! This is obviously impacting all sites across all divisions and once again highlights the importance of best practice on works on scaffolding and working at heights, along with the need for high quality hoardings and signage.

Bird’s eye

The drone has been up this month across multiple sites in our Country Division (before the high winds came). Phoebe has added drone flying to her role and captured some great footage from the skies. As a matter of course we keep photographic progress shots from all of our projects and produce a project book as each one gets handed over. It is always great to get a bird’s eye perspective.

New project

The Cotswolds team are delighted to have started on site at yet another Grade I listed project in the region. Working alongside a well established project team, we are excited to be working on an additional heritage asset in the region and are looking forward to the meticulous restoration works ahead.

Consistently striving

Castellum embraces a culture of team empowerment and we invest in the professional growth of our team, fostering a workplace of respect, collaboration and shared commitment to excellence. This month we all join to congratulate George Babarelu in our Cotswolds team who has just passed his Level 6 NVQ in Construction Site Management.

In other news

Majorly exciting – a baby has been born! This month, Brett has become a Daddy. Again! Florence Amelia Lane arrived on 4th September, weighing 7lbs and 5oz. What a little cracker and what a proud Brett! Florence has two big brothers, Freddie 7 and Oliver 5, and the whole Castellum team extend massive congratulations to Brett and his wife Amelia – now outnumbered!

Phoebe, our Marketing Assistant, is heading off this month to start her final year at The University of Liverpool where she is studying Marketing. She will continue working remotely for us from there whilst she completes her degree. Best of luck Phoebe – work (and play) hard!

The Cotswold office welcomed a new pup this month too. Charlie accompanies Bex to work every day and his client liaison skills are a site to behold. He shares his work space with Frodo and Bilbo who seem pleased to welcome him onboard.

And finally, Lyndon joined KSR Architects this month at their 24th Spirit of Belron Challenge, which brought together over 10,500 participants, including colleagues, friends, families, suppliers and partners.

The event spanned a ten-day virtual challenge and culminated in a day of sports at Dorney Lake, with involvement from more than 29 countries worldwide. Throughout the challenge, they cycled, ran, walked, swam and travelled by wheelchair, covering a total distance of over 325,000 kilometres.

Together, they raised over €2 million (and counting), which will greatly benefit children and young people in some of South Africa’s poorest regions, through their charity partner, Afrika Tikkun.

Lyndon said ‘KSR Architects were great hosts and the day went without a hitch with many of their office competing in either of the triathlons, or running events.’ He joined them for the day at Dorney Lake and scooped the Men’s Triathlon Sprint victory. A great effort all round!