Bushey Cemetery

Extending prayer and reflection space in a historic Jewish Cemetery

Bushey Cemetery is a Jewish cemetery, located on a 16-acre site of outstanding natural beauty in London’s Green Belt. The simple yet striking extension comprises two new prayer halls, a series of service buildings and increased burial site capacity from 43,000 to 60,000 graves.

The Jewish faith has a tenant that burial places are looked after in perpetuity; forever. The Bushey Cemetery extension provides new capacity and is the first new consecration of a United Synagogue burial site in the UK in 50 years. The project was delivered in two phases. The initial enabling works saw the installation of major civil engineering and landscaping works, including swales, weirs and ponds. This helps maintain natural drainage on-site and provides new wildlife habitats. The prayer halls and associated buildings formed phase two.

We worked with Waugh Thistleton Architects and landscape architects J and L Gibbons to deliver the extension that will continue serving London and Hertfordshire communities for the next 50 years. Our civil and structural engineers worked with Earth Structures, an Australian rammed earth construction specialist firm, to construct the seven-metre-high ceremonial walls.

Community & Public

Architect: Waugh Thistleton Architects
Client: United Synagogue
Location: London

Impact

The 7m rammed earth ceremonial walls gives the Bushey Cemetery and Prayer Halls a unique character, and a sense of sombre, calm beauty.

The UK climate is not ideal for rammed earth structures, which prefer dryer conditions. The material is typically unstable which shortens its lifespan, which is compromised by the site's flood risk. To address this, we stabilised the material by adding a small amount of cement and sand aggregate, which enabled it to achieve the modern forms in the design.

Different shades of the materials are visible in the stratification across its surface, and the 150mm layers of ramming sections can be seen as well, adding to the bare yet elegant aesthetic. While this external façade is solemn and austere, once inside the atmosphere is calm, inviting yet private, softened further by the use of timber and indirect soft light.

The noise attenuation effect of the material amplifies the tranquil yet solemn atmosphere required by funeral ceremonies.

The extension buildings have a 25-year design life and can be demounted, recycled and returned to the soil in line with Jewish traditions while an adjacent location is constructed.

Echoing the return to earth of the body, once all these new graves have been taken and the halls are no longer needed, the structures above ground have been carefully specified to be demounted and recycled, returning to the ground from which they came from, a fitting parallel to the human condition.

The use of rammed earth comes with strong sustainability credentials, including the time and cost efficiency of locally sourcing the raw materials and its manual construction methods. It uses significantly fewer natural resources than fired bricks or concrete walling. The material is also breathable and has a temperature stabilising effect. Given this and considering that the buildings were designed as sheltered external spaces, no insulation was required in addition to the material’s inherent high degree of thermal mass. The technique is likely to become increasingly popular and important for low carbon building.

With provisions for 17,000 new graves, the burial site now has a future capacity for 60,000 graves. Ensuring the Jewish community can continue to honour their dead in perpetuity.

Awards

2018 Stirling Prize Shortlisted
2018 RIBA National Award
2018 RIBA East Award
2017 WAF Best Completed Religious Building

History & Context

Founded shortly after the Second World War, for over 50 years Bushey Cemetery has been one of the most important Jewish burial sites in England.

The concept behind the design — a building that rises from the ground and, after serving its use, returns to the ground — reflects the imuportance Judaism places on bodies returning to the earth. The two prayer hall buildings are constructed from rammed earth, a traditional building material that is extremely robust, but can also biodegrade. The material is designed to last for 25 years, at which point the cemetery is estimated to be full and require another adjacent site and the current structure can be dismantled and recycled.

This project is part of the ongoing process of enlarging the cemetery so the community can continue honouring and protecting their dead.

Our Approach

Rising from and returning to the earth

It was challenging to develop a sympathetic cemetery extension that responded respectfully to the Jewish faith and provided greater capacity to support future burial demand.

The concept behind the design — a building that rises from the ground and, after serving its use, returns to the ground — reflects the importance Judaism places on bodies returning to the earth.

The two prayer hall buildings are constructed from rammed earth, a traditional building material that is extremely robust, but can also biodegrade. The material is designed to last for 25 years, at which point the cemetery is estimated to be full and require another adjacent site and the current structure can be dismantled and recycled.

Rammed earth is relatively unused and unknown in the UK. It consists of compacting, or ‘ramming’, a moistened mixture of soils into a formwork which, when dried, forms a dense, monolithic wall. Adding lime or cement into the mix improves strength and durability over time — this is known as Stabilised Rammed Earth (SRE).

7m-high rammed earth walls

The design had to be in keeping with the green belt landscape and address the site’s intrinsic flood risk. Rammed earth is a highly sustainable material because it is made from natural materials such as gravel, sand, silt and clay. In this project, we used materials found on site which reduced transport emissions.

The UK climate is not ideal for rammed earth structures, which prefer dryer conditions. The material is typically unstable which shortens its lifespan, which is compromised by the site's flood risk. To address this, we stabilised the material by adding a small amount of cement and sand aggregate, which enabled it to achieve the modern forms in the design.

International rammed earth expertise

Creating high-quality rammed earth structures is challenging. Because workmanship and experience were critical, we collaborated with Earth Structures, an organisation that has delivered thousands of rammed earth projects in Australia.

The early involvement of specialists meant that any potential drawbacks of the material or construction process could be addressed. Given that there is no official design standard for rammed earth, the engineering team had to justify the proposed design through very thorough repeat testing. Strength, durability, colour and texture were explored to provide a bespoke solution for the project.

The specialists’ involvement went as far as living on-site for the month. Half of this time was needed to build the walls, ensuring from a close distance that the finished product was of the highest quality.

Natural material selection

Timber is used extensively and sustainably, with glulam larch in the colonnade and English Oak throughout the interior.

Where appropriate modern materials were used, including the concrete foundations and plinths that keep the earth walls dry, exposed concrete and corten steel.

Engineering Solutions

We used materials found on site which reduced transport emissions.

The rammed earth walls, designed by Elliott Wood, reflect the makers’ craft in building them, utilising earth from the site via an ancient, sustainable and durable building method.

Choosing the correct soil mix is crucial to the success of the technique. At Bushey Cemetery, the scale of the 7m high walls, and the desire to keep much of the rammed earth walls exposed to the elements meant that cement SRE was chosen.

A number of test samples were produced, using a variety of locally sourced materials and assessed on the basis of colour, surface finish and strength. We then constructed a test panel using the chosen mix and left it exposed on site to test its weathering performance.
The key constituents of the mix are coarse aggregates and sands, binder material, water and plasticiser.

The earth mix was then compacted into the formwork with pneumatic rammers in 600mm thick layers, matching the height of the formwork panels, which were then added incrementally to allow access for ramming. This process introduces horizontal formwork lines and tie-holes, as well as natural colour variation between the rammed sections.

Vertical expansion joints were specified to prevent cracking of the walls during the initial drying phase and to accommodate thermal expansion caused by exposure both internally and externally. The spacing of the joints was matched with the width of the subcontractor’s formwork, and emphasised with chamfered arises to ensure a crisp finish.

The landscape architect, J & L Gibbons, ensured the soft landscaping and routes around the main buildings inspired tranquillity, reverence and a sense of calm for those visiting the site.

Following this vision, our Development Infrastructure team devised a sustainable landscape-led surface water strategy, which incorporated attenuation basins, swales, and permeable construction for both the primary and overflow parking areas.

The original site, which was previously arable land with no formal surface water drainage system, necessitated thoughtful planning from concept stage, in order to mimic natural flow paths and hydrogeology across the development. New roads, footpaths, buildings and burial plots were constructed with this in mind. Our team were also tasked with thinking 50 years ahead to accommodate the expansion of the cemetery, devising a plan that would suit both the initial 15% and the anticipated 43% of hard surface coverage.

The soft landscape-led approach to site infrastructure aligned with the overall integration of sustainability practices throughout the project. Measures introduced not only promote biodiversity and amenity values but also create a serene water’s edge setting for mourners to remember loved ones throughout all stages of grief.

RIBA Stirling Prize 2018: Bushey Cemetery

A poetic response

"The limited number of buildings, the simplicity of the forms and expressionist choice of materials all reflect the symbolism of burial to the Jewish community. This project will be just a stage in the ongoing process of enlarging the cemetery so that the community can continue to honour and protect their dead. The fact that the rammed earth walls of the prayer hall will return to the earth once the cemetery is full and has to be extended again, is a poetic response to the programme for the cemetery and the traditions of the Jewish faith."

Stephen Rajbenbach, United Synagogue

Construction

The project was delivered in two phases. The initial enabling works phase involved the installation of major civil engineering and landscaping works, in which a series of swales, weirs and ponds were introduced to help maintain natural drainage on the site and provide new habitats for wildlife.

The second phase saw the construction of the prayer halls and associated buildings.