Comment: Adrian Attwood from DBR talks about helping the existing built heritage cope with climate change

Adrian Attwood

Adrian Attwood, Executive Director of DBR, explains why it's important to talk to a specialist about preparing the built heritage for climate change.

Adrian Attwood, Executive Director of DBR, a specialist conservation company dealing with the cleaning and repair of historic fabric and the regeneration of historic buildings, explains why it is worth talking to a specialist about preparing historic buildings for climate change.

The conversation around climate change is continually heating-up (pun intended!). Across construction there’s now a concerted effort to drive down emissions and prove the sector is taking Net Zero targets seriously.

However, it’s not just about reversing climate change in the long term. It’s about adapting our existing stock in the here and now. Nowhere is this more important than in our heritage buildings and landmarks, none of which were built with much (or any) idea that we would eventually be faced with an environmental crisis.

Particularly, architects in bygone eras would not have had the knowledge or methods for reinforcing buildings against the erratic weather patterns or fluctuating temperatures we’re currently experiencing.

One significant issue which needs to be addressed is the increased risk of flooding.

A recent report from The Met Office indicated that the UK has become noticeably wetter over the past 50 years, particularly in the period from 2011 to 2020, when there was a 9% rise in rainfall. The report also suggested that these levels could increase in line with the heightened likelihood of extreme meteorological events.

As we experienced this year, climate change has brought on other meteorological events in the form of extreme heat waves. Hot weather can be detrimental to historic properties – both for the physical fabric of the spaces and for the visitors.

To combat this, we have recommended to our conservation team and other heritage professionals to consider the implementation of heat reflecting systems – blinds or shutters, awnings over window and doorframes (so long as it does not detract from the original façade) – and upgraded building insulation.

These simple solutions can reduce heat gain as well as heat loss within a historic property. Insulation in roofs is a particularly quick and inexpensive solution for energy efficiency.

Many historic buildings are vulnerable to flooding and, of course, were not originally built to withstand massive deluges. Depending on the scale of the issue, damage can range from the minimal to the extensive, but in each case the remediation and restoration is costly.

In the worst-case scenario, irreparable damage or structural collapse can occur, requiring complete rebuild and potential loss of interior finishes and works of art.

So it’s far more prudent and cost-effective in the long-term to work with specialist contractors to reinforce the structural integrity of our heritage stock and provide optimal defence against the elements.

We in the conservation construction profession now have the methods and the tools to com-bat these changing circumstances and mitigate the potential effects. Many of these implementations are far less complex, and therefore easier to address, than one might think.

While there are many different ways flooding can occur, whether it’s river, coastal or ground-water, the approaches for mitigating flood damage are much the same in each instance. These approaches can be encompassed in two schools of thought: flood-resistance and flood-resilience.

Flood-resistance looks at ways to reduce the amount of water actually entering a property during a flood, and flood-resilience seeks to reduce the amount of damage caused when water does enter a property.

At DBR, much of the work we undertake is a combination of the two, with the aim of futureproofing the structure of the building.

A common task for us is improving main water drainage, enhancing existing systems to handle higher occurrences of rainfall. This includes the repair of, and incorporation of, strategically positioned lead sumps, as well as work to increase their capacity, complemented by repaired, replaced and extra internal rainwater pipes along with overflows and blockage warning systems.

One avenue of flood mitigation DBR was involved in was in raising the railing base on the riverside of the Thames.

This strengthened the embankment to accommodate rising river levels and the increased likelihood of erosion, which could lead to subsistence and structural damage. It also protected the embankment from the impact of the Thames Clippers, which regularly pass the site, creating surges that can wash over the riverside masonry, causing significant damage.

Importantly, the works undertaken need to be conducted with the utmost sensitivity to any building’s fabric, to prevent any unnecessary damage that could arise from heavy-handed or careless installation.

Our recent adaptive work at the Old Royal Naval College, Greenwich, where the famous Painted Hall is sited, offers a perfect example of this careful, considered approach. The work involved designing and building-in optimal flood defence with an eye on maintaining the integrity and appearance of historic fabric.

But flooding is just the tip of an iceberg of climatic issues that historic assets need to be pre-pared for.

Many in the conservation construction sector will remember when a massive chunk of stone fell from the Palace of Westminster’s Victoria Tower in 2018, subsequently attributable to in-creased temperature fluctuations that loosened the iron cramps holding the stone in place. It prompted a regular survey of the landmark’s stonework to spot the early signs of climate-caused damage and address them immediately.

This is all before you look at the requirements to bring these structures up to modern building standards, which comes with its own challenges.

For example, the fabric of these structures needs to breathe, so hermetic sealing is a challenge. Also, preventing energy loss is now an essential consideration, needing to be ad-dressed on a case-by-case basis, although there are a number of neat solutions. For example, on the Liberty’s conservation undertaking, we used solar reflecting glass to reduce solar gains, keeping the building cool and protecting interior timber panelling from the effects of overheating.

All encompassing, these challenges are wide-ranging with no simple answers. However, there can be no question that, if we want to maintain our heritage buildings and historic land-marks, we need futureproofing against climate change to be a central component of future renovation and restoration projects.

Ultimately, generations to come will thank us for making the investment now to conserve our rich and diverse architectural tapestry – something which I believe we all want our descendants to enjoy in full.