Site Lines: A heritage refurb checklist

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Simon Castle from Chisholm & Winch discusses the varied, but essential considerations that architects need to bear in mind when approaching listed building renovations

According to Historic England, there are estimated to be around 500,000 listed buildings on the National Heritage List for England (NHLE). A listing marks and celebrates a building’s special architectural and historic interest, and protects it for future generations. The older a building is, and the fewer the surviving examples of its kind, the more likely it is to be listed. Heritage restoration is the process of accurately recreating the character, features, and structure of a building, as it would have been at a particular time.

This is one of the first and most important aspects to consider during heritage renovation, as these buildings are so precious to our built environment, partly as they act as a window to our history. Heritage restoration is also an economical and environmentally responsible practice. It’s a delicate process that requires careful planning and execution to preserve the historical significance and aesthetic value of a building while simultaneously making it fit for modern purposes.

The challenge is that most older properties were not constructed for 21st century tastes, or performance. If they are to be practical, sustainable, attractive buildings for the modern era, there is a delicate balance to be struck between preservation and innovation. We must maintain the character and integrity of the existing structure, while updating it for a new generation of use.

Historical significance

Before beginning any refurbishment work, it is important to understand the historical context of the building, as well as any regulations or guidelines that may apply to the renovation.

In some cases, certain aspects of the building may need to be preserved or restored to maintain the integrity of the structure which can involve using traditional building
techniques and materials or replicating certain features to match the original design.

Chisholm & Winch worked on a project for The Crown Estate to upgrade a five-storey Regency house in west London, located between Mayfair and St James’s, and provide luxurious private rental accommodation.

Some of the rooms within the building have original Georgian timber panelling; our remit included refurbishing these, as well as matching new timber panelling to the original where replacement was required, and restoring those areas that could be preserved.

One of the showpiece elements of the project was a new staircase that curls through the centre of the property. Here, new balustrades and bannisters, in keeping with the period, were installed to create a feature that is not a pastiche of the original, but immediately references the period.

Oak floors throughout the building marry traditional materials with contemporary tastes, and bespoke joinery across the luxury kitchen, custom-fitted wardrobes, spacious wine cellar and heritage doors echoes the workmanship of the original building while updating it with contemporary style.

Meticulous planning

Developing a comprehensive plan that includes realistic timelines, budgets and a detailed outline of the renovation helps to reduce risk and potential downtime throughout the project. Some construction companies have their own experienced project managers that plan every project down to the very last detail – so they know exactly what is being projected and what can be delivered. Timings and budgets need to be communicated to all stakeholders so that everyone is aware of any upcoming variations.

Materials & techniques

The materials and techniques used in a heritage renovation project are essential to preserving the historical significance and aesthetic value of the building.

In some cases, it may be necessary to source specialised materials or employ traditional building techniques that are no longer commonly used. Older buildings are often made with unique and valuable materials and incorporate details such as decorative facades, lime mortar brick pointing, glasswork, and traditional methods of workmanship that are emblematic of their time. These features give older buildings their own identity and character, often making them more interesting and aesthetically attractive than many modern buildings. However, preserving these features needs to be coupled with modern construction methods and materials to ensure the safety and durability of the building.

Structural considerations

The structural integrity of a heritage building must also be carefully considered during a renovation project, to avoid compromising its safety and stability.

In some cases, it may be necessary to reinforce or repair certain elements of the building to ensure its structural integrity. This would involve working with a structural engineer
to assess the building and develop a plan for any necessary repairs or reinforcements.

Regulations & permits

Heritage buildings are often subject to specific regulations and permit requirements that must be followed during a renovation project. It is important to research and understand these requirements before beginning any work.

This could involve working with local government agencies and heritage preservation groups to obtain the necessary approvals. Any contractors or subcontractors involved in the project need to be knowledgeable about the regulations and requirements that apply.

Project focus

There are many high street buildings that are no longer suited to their original purpose, but which have architectural value. An excellent example of this, and the heritage restoration work undertaken by Chisholm & Winch, is the conservation of a Grade II listed former temperance hall in south east London, plus an additional new build extension. The project turned a piece of Lewisham’s history into a new community hub for the Tab Church.

The building had already undergone several reinventions during its lifetime. A tea hall in the 1920s and a snooker hall for several years; it had been left to decay for the past four decades before The Tab took it on. With water seeping through the roof, some of the structure was compromised so the task of refurbishment involved making good the original structure, modifying the building for a new purpose and preserving features that connect the property’s history with its future.

The new build elements bring contemporary community spaces and office areas to the site, and much of the refurbishment delivers contemporary facilities and aesthetics. The main hall includes a state-of-the-art auditorium with a dramatic walk-in baptism pool, a new mezzanine level, and underfloor heating.

The new additions have been delivered with respect for the original building. For example, bespoke steelwork makes the property more structurally robust, while providing a feature that’s in-keeping with the early 20th century building. A rooflight installed at the apex of the restored roof’s pitch allows natural light to flood the previously gloomy space, using a contemporary feature to showcase the craftsmanship of the original building. And of course, restoring original features and carefully selecting materials to connect old and new is integral to the aims of a project like this, so the roof was stripped and re-built. New trusses and insulation were installed to ensure the building is robust and delivers 21st century thermal performance, while the old trusses were restored and reinstated as a decorative feature and the original slates have been re-used wherever possible.

In order to preserve an original scroll detail, a gable wall was moved back one gridline into the footprint of the building to enable construction of a new brick slip external wall while retaining the feature. Decisions like this may add layers of complexity to the build, but they also ensure that upgrading the heritage building adds to its legacy, without detracting from it.

Collaboration supports success

At every stage of heritage renovation project, collaboration between the client, the architect and the contractor ensures that decisions made during the refurbishment of the building capitalise on opportunities to both preserve and improve the property, while tailoring the accommodation to its contemporary use.

Whether the building is for residential or commercial use, heritage refurbishment is not about creating museum pieces, but about delivering our future built environment without destroying our past.

Simon Castle is managing director of Chisholm & Winch