A complex procedure restored the full historical interest

JCA Team:
David Rhodes
Project Design Team:
Johnston Cave Associates (Architects) CDM&A 
(Project management) 
Fleur Rossdale 
(Interiors Consultant) 
David Mendel 
(Specialist Decorations) 
CGS (Quantity Surveyor) 
Andrew Waring Associates 
(Structural Engineers) 
Environmental Engineering Partnership 
(Services Engineers)

Principal contractor: 
Boshers (Cholsey) Ltd
Project type:
Refurbishment & Extensions
Project year: 2015
Photographer: William Pearce

The client’s brief was simple enough; form extensions and alterations to their Grade II* listed 16th Century Manor to provide a comfortable home with four family bedrooms, plus a further eight with en-suite facilities – while retaining the historic features and fabric. 

Getting it done was another matter.

A particular challenge was that a previous owner had entered into a restrictive covenant in favour of the National Trust. This had the effect that all proposals had to comply not only with the usual planning and Listed Building consents, but also had to pass the Trusts’ scrutiny. 

Gaining consent under the covenant involved meeting with a delegation from the National Trust’s Architectural Review Panel to tour the Manor and explain the proposals in context. With the Panel comprising of professionals from many different fields, working closely with the Trust gave the opportunity for the designs to be thoroughly tested and refined, and this culminated in the granting of all the necessary approvals to allow the construction work to commence. 

Once on site, a particular obstacle was that our approved design required significant earth-works to conceal the majority of the swimming pool Hall beneath ground level, that our client loved and was set on. Given that the Manor is located within a small village, there was a very real limit to the size of the plant that could be brought to site to complete the task.

A structural solution was developed with contiguous piles, some extending 45 metres beneath the surface. Small - just 450mm diameter - piles were specified which then allowed the use of a smaller piling rig than usual to be brought through the village and to the site. 

Additionally, the main roof was identified as being a bat roost. As the works involved the replacement of the roof tiles, installation of new underlay and the fitting of insulation, there was an extremely tight window in which the works could be carried out.

The re-roofing was a very well co-ordinated operation. All works were completed within just eight weeks with a further complication being that the ecologist specified that at least half of the roof area needed to be intact for any given period. Careful record drawings of exactly where ventilating tiles were located were prepared to ensure that everything went back in identical positions as these tiles are often used by bats for access. In addition, hundreds of tiles were tweaked to provide bat habitats, and special lead tiles were formed to further improve the access for bats. 

Our design ensured that much of the infrastructure is hidden below ground and from view. The double-height Roman themed swimming pool Hall for example, rises above ground only to the height of a normal garden wall and light floods in from a substantial glazed lantern. Even the Doric columns provide routes for air-handling duct-work, with a continuous ventilation slot to the perimeter to ensure that the environment remains stable. A custom blend of mosaics provide the intended water colour. 

To avoid the use of dermatologically abrasive chemicals, the treatment plant to the new swimming pool avoids the use of chlorine altogether, instead treating the water with ozone and hydrogen peroxide. The plant room is located to a basement beneath the pool; this allows all sides of the pool structure to be accessed from below ground level to simplify maintenance access to light fittings, filter connections and the like. 

In keeping with the local vernacular and being true to the 16th Century origin of the house, the external elevations are, in the main, flintwork with stone and brick dressings. Great care was taken with the detail to ensure that differing styles and treatment of the flint read clearly and as a homogenous whole. The rather awkward original courtyard garden has been transformed into a properly usable space.

By fully integrating the services required by a modern home, the existing unsightly boxings that were littered throughout have been removed and the full historical interest has been restored. Traditional conservation methods and materials were used where appropriate to ensure that the works were of a high quality.

Today the simplicity and elegance of the solution and facilities belies the complexities of the task.