Design-led Architects based in Gravesend, Kent delivering highly workable contemporary and innovative design solutions to challenging briefs and tight budgets

How Not to Kill a Building

Kasan Goh of Clay Architecture will be giving a talk at Canterbury School of Architecture at 5.30pm on the 19th of January 2016:

This talk is something I've been kicking about for a while, and the title came from a conversation I had over coffee with Allan Atlee of CSA some time ago, where I was mouthing out about how much bloody work it took just to keep projects alive. We thought it'll be a great idea to base a talk around the seldom-talked about, less glamorous aspects of being an architect, and some of the challenges of small practice in the regions. About as far removed from Starchitecture as you can get. Raymond Quek invited me to test drive the talk at De Montford Leicester School of Architecture last November, where it generated a lively Q&A, now I'm looking forward to chatting to the students at CSA.

About Clays:
‘… the pattern for most architectural firms is to set up in London ( or another big city ), and compete in a hot soup of young practices, using every opportunity to create small photogenic projects to catapault them to the holy grail of public projects. Breaking the mould, Camilla Prizeman and Kasan Goh, a husband and wife team who met at the Architectural Association school in 1991, set out to create a different sort of practice when they moved away to Gravesend in Kent in 2000. Their unusual strategy has paid off and… they have created a practice steeped in its history and place in a way that is hard to achieve in the capital. Prizeman and Goh are more interested in the way that people will react to and behave in their buildings, than what the projects look like in magazines- though they do look extremely good. As Prizeman and Goh say: ‘There may be something to be learnt from concentrating on the design of normal and everyday things and places.’

 Vicky Richardson, Blueprint, 2008



Where has the year gone? Blink and its October.     
  4 bits of news to report.

  Medway Archives

This month Clays won a mini-competition to convert the former Strood Library into a new Medway Archives and Local History Centre. Clay’s design proposals involve stripping back and interventions which are more in keeping with the original 1972 Colcutt & Hamp Architects design; windows blocked in to protect historic documents from light damage will be filled with illuminated billboards of selected images from materials found in the archive.


  Chatham & Clarendon Grammar School, Ramsgate 
Clay’s supporting information and detailed conservation condition surveys of the historic Grade II Listed Chatham House and early 20th Century Clarendon House were instrumental in helping the Academy secure £2.3m in Education Funding Agency money in February. This follows emergency masonry work carried out by Clays and master stonemason David Adamson in early 2014, when Clay director Camilla Prizeman spotted a dangerously weathered stone finial during a visit to the school.

Gravesend Borough Market

Clay’s scheme for regenerating Gravesend Borough Market’s indoor market hall and old fish hall was awarded £1.8m from the Big Lottery Grant Coastal Communities Fund in January. The fund invests in coastal towns to help them achieve their economic potential; the scheme brings natural light into the dark halls, and include a mixture of fixed and temporary stalls to improve the quality and variety of traders, artisans, crafters, food and vendors stalls in the historic market (which was first granted a charter in 1268). The development will help create 35 new jobs in the area and revitalise the town centre. Work is due to start towards the end of this year.

Find of old drawings

Following the success of Making Places, Changing People, local historian Christoph Bull contacted us in September: a cache of old drawings and documents were found in the loft of a garage building off Parrock Street where the George Clay Partnership had its offices.

Clay directors Kasan and Camilla, archivists from the Kent History Centre and the Architectural Association School of Architecture visited the site to sieve through, select and retrieve historic drawings and documents. Amongst the finds are drawings from the late 19th century and early 20th century attributed to Adolphus Rayner, master builder; and Rayner, Kidwell and Bridgland architects & surveyors; Bridgeland & Clay architects & surveyors; George E Clay Architect and the George Clay Partnership.

Finds included George Inis Clay’s student portfolio from the Architectural Association (1928 to 1932), drawings of pubs, shops and houses, as well as blueprints for a gun cotton press and documents relating to jobs for Curtis & Harvey Limited adding fuel to the theory that Clays had at least some involvement in the explosive factory at Cliffe ( circa 1910s to 1920).



Artist’s impression of the proposed Medway Archive

Chatham House, Chatham & Clarendon Grammar School

Early sketch from Clay’s aspirations masterplan for Gravesend Borough Market

Sample drawing retrieved from the find. Date June 1912, by Bridgland and Clay




The Art of Feasibility

How to start up a school building project— the art of feasibility

Building works are costly to commission, but the consequences of poorly planned works are even costlier if they go wrong during or after construction.

Schools should seek expert advice in the planning of building works— a well-thought out feasibility study completed by an expert will highlight the risks and costs of planned building works, to enable the school make a decision on whether or not to proceed with the work, and, if the school does decide to proceed with the work, will provide the foundation for the justification for funding.

Project managers, surveyors and even builders may be able to carry out or contribute to a feasibility study, but in our opinion an architect (at senior, partner or director level) experienced in school projects will be best placed to provide the rounded knowledge that is required to carry out a thorough feasibility study at the planning stage. Beware of practices who assign feasibility studies to junior or less experienced staff to complete.

For example, we recently worked on a school re-glazing and re-cladding job on which an earlier feasibility study had been commissioned from a surveyor. Although, the surveyor had done a fair job in analysing the concrete failure and estimating the cost of the re-glazing and re-cladding works, they did not have sufficient skill or experience address the following issues:

1. The fact that the classrooms overheated due to solar gain in summer. There are software packages, Class Cool and Class Vent, which can be used to calculate the correct glass specification to reduce solar gain, and the correct opening window sizes to sufficiently ventilate a classroom. These requirements are not found in the Building Regulations Approved Document but in DFES’ Building Bulletin 101, which has the same legislative weight as the approved document. 

2. The fact that concrete failure was caused by approximately 1 km of cold bridging— interstitial condensation within the exposed building structure— and that the new cladding and glazing should be designed to remove or prevent future cold bridging in order to avoid a continuation or escalation of the problem. 

3. The fact that removal of failed concrete from a reinforced concrete frame building is noisy work and needs to be carefully programmed to reduce affecting normal school business (unless classrooms are decanted, at additional cost). 

4. The fact that air-conditioning cables running across the building elevation needed to be rerouted, and the air-conditioning units sited next to the windows and cladding needed to be decommissioned for the duration of the building works. The existing air conditioning units were old and were unlikely to restart after decommissioning and so needed to be replaced.

Unfortunately, the school had bid for, and obtained funding based on the recommendations of the earlier feasibility study. Because the cost and complexity of the work had been underestimated by the surveyor, we had to carry out a number of value engineering (cost cutting) exercises to enable the project to be completed despite the oversights. The school could have had a better result if they had gotten a better feasibility in the first place.

Do not be shy of seeking a second opinion or getting a reference for your architect / surveyor etc.

An experienced professional will advise the school on what additional consultants are required (structural engineer and mechanical and electrical services engineer for example) in order to plan the job properly.

It is important that necessary surveys are carried out at an early stage to gather as much relevant data as possible. See these as a necessary but preventative cost— surveys help to identify and highlight potential risks (and hidden costs) to the project. Your architect will advise you on the surveys required for the feasibility study.  

Feasibility studies and reports come in all shapes in sizes, but are only worth their weight if they achieve their objective. This varies from project to project, but typically a feasibility study should aim to achieve the following:

  • Clarify and test the clients brief. The brief may be a single project— such as a classroom, staff room extension or sixth form centre— or a group of projects or list of building defects that need addressing (leaky rooflight above classroom X, cracked concrete above the hall, overheating of classrooms in summer etc.). 

  • Identify and appraise different options for achieving the requirements of the brief in a way that will enable the school to decide which option is the most appropriate or feasible option to implement. This should include a cost estimate of the various options (typically estimated by a quantity surveyor or building estimator, then compiled and presented by an architect). 

  • Identify risks and other hidden or abnormal costs, and recommend how these risks may be avoided or reduced, and advise on the cost of these risks or the cost of avoiding these risks. An example of a common risk would be: asbestos removal. 

  • Draft a programme for building work and advise on the best way to procure a competitive price for completing the work. 

A feasibility study is NOT:

  • A design. It is the necessary groundwork at the early stages of a project which will help clarify the project brief. Repair and maintenance work may require very little, or no design input at all, but it may need the specialist knowledge of a designer (for example, conservation knowledge if working on a historic building more than 60 years old.)

 A good design:
  • Meets the criteria set out in a good feasibility study.  

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Case Study: Concrete Repairs to ‘60s RC frame buildings

The main teaching block before refurbishment

Queen Elizabeth Grammar School, Faversham 

The main teaching block and science block of the school were built in 1967. Both are reinforced concrete frame buildings that featured exposed reinforced concrete columns and window transoms; the main block has reinforced concrete balconies on the rear façade. 

The exposed concrete was in very poor condition; sections of concrete were spalling and had fallen off, exposing corroded steel reinforcement— an ongoing maintenance and health and safety problem; repairs were undertaken in 2001 and 2005 but the repairs were themselves in poor condition; the lightweight mortar failed to bind and was spalling in areas. 

Exposed concrete window mullions spalling throughout the block facade

The walls of the buildings had no thermal insulation; the existing windows were clear float single glazed metal Crittall windows. Classrooms are located behind the east and south elevations; the rooms suffered from solar gain and were hot and uncomfortable in summer— a situation exacerbated in the IT suites where air-conditioning was required to counteract the additional heat gained from IT equipment ( in these rooms, internal blinds on the windows were almost permanently left down to try and reduce heat gain and solar glare from the afternoon sun ). In winter, the building did not retain heat well and the school’s energy bills were high. 

Exposed reinforcement to the balconies

Clays were commissioned by the school to carry out concrete repairs and refurbish the façade of the main and science blocks; following the disappointment of being dropped from the BSF programme in 2010, the school wanted a fresh new look for the school buildings to send a positive message to the school community. Clays also carried out a feasibility study that demonstrated that extending the blocks to create a new Sixth Form Centre would be uneconomic— extension work would bear the extra-over costs of temporary accommodation for 16 classrooms; the original buildings had not been designed for disproportionate collapse and the cost of structural work for any extension would be disproportionate to the net area gain. 

Turning our attention to the façade works, a heat gain and natural ventilation analysis was carried out using Classcool and Classvent software. 

Clays developed a refurbishment strategy that involved:

 • The removal of all horizontal concrete window transoms and repair and protection of exposed oxidised metal reinforcement to the balconies. 

• Reducing the number of windows to the IT suites to the minimum required for natural ventilation to BB101. Solid composite panels rather than clear glass panes were specified on some of the windows in order to further reduce heat gain and solar glare. 

• Replacing the existing Crittall windows with double-glazed aluminium windows designed to be fixed in front of the exposed concrete columns, thereby protecting the reinforced concrete elements from the weather, reducing cold bridging, interstitial condensation and further concrete failure. The new windows had a maximum U-value of 1.8 W/m2K and were doubled-glazed with an outer pane of low E glass with a solar transmittance of 0.4 or below— resulting in a 52% reduction in solar transmittance without significant loss of daylight transmittance. 

• Replacing the existing ‘fish-scale’ tile cladding with rainscreen cladding ( cedar on the east façade and Trespa on the west façade— which is in shadow and not suitable for timber ) to achieve a maximum U-value of 0.28 W/m2K. 

The contract, managed by Clays, was let for tender and completed, within a tight budget, in 12 weeks in time for the 2012-2013 academic year. 

In the process, 1,958Lm of defective concrete and cold bridging have been encased / removed. The rooms now perform significantly better which will prove beneficial to running costs and comfort— in summer, blinds are now left up and lights left off. The school is very happy with the look of the refurbished blocks. 

The main teaching block after refurbishment

View of the refurbished teaching block

Image/s: Before images by Clay, after images by Dilip Hirani


Kent Design Award 2012 for Best Public Building ( Education )

Walderslade Primary School

Last night, at the Marlowe Theatre in Canterbury, along with 6 other projects ( out of 94 entrees ), Walderslade Primary School won a Kent Design Award ( held tri-annually ). Amongst the other six winners are the Turner Centre, Margate by David Chipperfield Architects, and Dover Esplanade by London practice Tonkin Liu.

We won in the Public Buildings Education category, a tough category-- to be honest I was expecting a commendation at best so the award came as a shock. Walderslade was a difficult job, the D&B-ness shows through in places in the finished building. We didn't even make it into the public buildings category on the first shortlist-- we'd originally been placed in the energy performance category, but the judges were pleasantly surprised when they visited the site, apparently the building looked 'better in reality than in the pictures' ( no disrespect to our photographer Quintin-- we didn't have his final photos at the time of entry ) unlike other entrees that looked 'better in the pictures than in reality'. So the judges decided to upgrade Walderslade to the public building category.

There we were up against stiff competition, such as the crafted elegance of the Sevenoaks School Performing Arts Centre by Tim Ronalds Architects ( Tim was a technical tutor when I was an architecture student in the late '80s ), and Jestico + Whiles’ £35m Cornwallis Academy.

But the judges later told us how much they liked the project: what tipped the balance in the end was how, given the constraints of a very difficult and challenging site and the technical complexity of building the design in response to the site, the team managed to provide a 'great space for the kids'. 'Whereas anyone can build a good building in a beautiful site using a name architect'. I'll take 'great space for the kids' as a compliment for the team.

We like to thank the team for their hard work, and to thank Medway Council for commissioning us in the first place ( if anyone has Lexley Maxted and Steve Gilberthorpe's email addresses please forward this to them as thanks for getting us to do the first feasibility in 2003 ). Medway has been one of our best clients, with whom we've worked 9 of the 12 years Camilla and I have been running Clays. Walderslade wouldn't have been possible without the experience and valuable lessons gained on other Medway jobs such as Fair View School, Danecourt School, St James Sure Start, Medway Park to name a few.

So it was good to sneak in and nick one on behalf of Medway at a KCC award ceremony :-)

Have a good weekend!

Walderslade Roof
Walderslade Internal

Image/s: Quintin Lake