ERNEST COOK TRUST – FAIRFORD
RENOVATION AND EXTENSION OF HEAD OFFICE
Fairford Park Estate has been altered and redesigned significantly over its history. The house was built by Valentine Strong and his son in the 17th century with the walled garden to the west. Various outbuildings have been added around the walls of the walled garden over time.These include glass houses to the north of the walled garden, that have now been demolished, and the existing head office buildings that were previously stables and coach houses.
Existing Site Plan
Existing Ground Floor Plan
Since the pre-application, care has been taken to minimise the alteration of the historic existing buildings. The spaces have been planned so that only the 20th century additions (partitions, lowered ceilings, mezzanine and modern window fittings) are required to be removed. Apart from the resizing of some openings to bring light into the building or provide access, the original masonry buildings remain as existing.
Proposed Site Plan
Proposed Ground Floor Plan
Proposed plan of entrance courtyard, showing re-organised car parking, new visitor entrance and planting areas
The building is accessed by visitors from the Entrance Courtyard via level access through the reinstated coach house doors in the Main Building.The garden is visible from an enlarged reception space with various scales of meeting space accessible via direct access. The masonry walls remain largely unaltered with only the 20th Century additions removed. The mezzanine is also removed creating high ceiling heights for the more public facilities. To restrain the existing walls following the removal of the mezzanine, tension rods are installed to support the walls at eaves level. These add character whilst referencing the existing tension rods in the Kennels and stables buildings. Underpinning of the existing building is only potentially required locally where each strip foundation of the Cloister meets the existing building foundations.
East west section through the Main Building and Cloister
The cloister links the existing buildings and the Pavilion internally, but also provides a central shared space, to allow integrated and collaborative working. The garden is accessible via large doors with level access. A large rooflight that spans the length of the space and large windows provide plenty of light. The space allows staff and visitors to enjoy the garden in all weather for work as well as at break times.
Cloister Internal View
The Kennels floor level is higher than the Main Building (due to building around existing foundation levels and building datums). The Kennels are accessed internally via steps or a platform lift within the Cloister. A staff entrance is now provided with a ‘muddy boots’ entrance area with level access via a path to the new proposed staff parking area. The 20th Century internal partitions and lowered ceiling are removed to create open plan office spaces to the west with access to the gardens through existing openings. Ancillary spaces are located to the east where less natural light is provided.
North south section through the Pavilion and the Kennels
The Pavilion provides the Trust with much needed additional space for their growing team. Meeting space is provided as well as double aspect open plan office space. Two offices are placed at the west end of the space, required for the privacy of senior members of staff. The partitions that surround these spaces are designed to be removable, should the trust or future occupants wish to expand the open plan space in the future.
01 – Oak timber framed triple glazing
02 – Powder coated metal framed triple glazing
03 – Oak boarded door (triple glazed if glazing shown)
04 – Painted timber framed double glazed window to match existing
05 – Crittall style metal framed glazing
06 – Existing crittall style metal frame glazing
07 – Oak timber shingles
08 – Oak timber boarding
9 – Douglas fir timber boarding
10 – Douglas fir solid timber element
11 – Sinusoidal profile metal roof (RAL colour to match roof slate)
12 – Natural slate tiles to match existing
13 – Flush rooflight powder coated to match roof finish
14 – Existing brickwork (repaired where required)
15 – Existing stonework (repaired where required)
16 – As existing
17 – Staddle stone in Cotswolds stone
- Oak timber framed triple glazing
- Powder coated metal framed triple glazing
- Oak boarded door (triple glazed if glazing shown)
- Painted timber framed double glazed window to match existing
- Crittall style metal framed glazing
- Existing crittall style metal frame glazing
- Oak timber shingles
- Oak timber boarding
- Douglas fir timber boarding
- Douglas fir solid timber element
- Sinusoidal profile metal roof (RAL colour to match roof slate)
- Natural slate tiles to match existing
- Flush rooflight powder coated to match roof finish
- Existing brickwork (repaired where required)
- Existing stonework (repaired where required)
- As existing
- Staddle stone in Cotswolds stone
The facade cladding of the pavilion is proposed to be an oak shingle with a base of Douglas Fir boarding, similar to the cladding on the North Wall Arts Centre in Oxford. The untreated timber will turn a silvery grey colour over time when exposed to weathering.
The Douglas Fir timber columns that line the facade of the extension are raised up off the ground on staddle stones.This will minimise the effects of weathering whilst referencing tradition-al timber agricultural buildings.
The roof is proposed to be clad with sinusoidal metal roofing.This contemporary material is extremely tough and lightweight.The form of the cladding is similar to that used on agricultural buildings around the site and in the local area. The roofing will provide a crisp edge to the roof and allow water to run off into channels to pro- vide water for attenuation planting in the North Garden.
Pavers found in the existing stables building inspire the floor finish of the Cloister and the Reception space located behind the large coach house doors.The finish references the previous use of the coach house and reflects the external nature of the Cloister that opens out onto the garden.
The pavilion shields the sun and provides sheltered external space. Water falls from the roof into water channels that feed into attenuation planting.
The Cloister design includes a flat roof with rooflights rather than a fully glazed pitched roof (as pre-planning advice recommended). This is partly because a pitched roof would form awkward geometry with the Kennels building and a flat roof maximises the space available whilst aligning with the Kennels’ eaves. It is also because occupant discomfort from extreme temperatures and excessive daylight would occur if the roof was fully glazed.
The Cloister links the buildings with a minimal structure that brings light into the existing and gives views to the garden. Paired with the additional insulation to the existing buildings the Cloister helps provide thermal comfort for users.
The roof of the pavilion is designed without a gutter to allow water to fall from its edges into water channels around the buildings perimeter. Water is to be collected and used in the north garden attenuation planting.
A thermal comfort assessment has been conducted to demonstrate the whole design is unlikely to overheat during summertime periods. CIBSE TM52 The Limits of Thermal Comfort (2013) has been used as a guide for what are regarded as acceptable thermal conditions.
The Cloister and Pavilion are classified as a large extension because they have a total useful floor area that is both over 100m² and greater than 25% of the existing building’s floor area. This means Part L2A regulations are applicable to the new areas which includes the requirement for carbon calculations. An IES simulation demonstrates these areas are compliant with Part L2A; the Building Emission Rate is 26.1% better than the Target Emission Rate.
The Pavilion and Cloister structural frame and cladding is to be made from 100% UK sourced timber from forests local to the site to reduce the embodied carbon energy of the design.
A key part of the Trust’s brief is the desire for a sustainable building with a low carbon footprint. Two key design concepts achieve this: retrofitting the existing buildings and reducing the energy consumption of the development.
Retrofitting is the most sustainable way of building to meet our future needs whilst reducing energy consumption.
The existing buildings at The Ernest Cook Trust are highly inefficient in terms of energy and are difficult to keep warm in winter.This is because the solid stone walls have no insulation and the windows are single glazed and in poor condition. Overheating in the summer also occurs in the small offices within the roof space of the stables building.As such these spaces are not fit for purpose.