One of the most significant impacts of climate change affecting traditional Scottish buildings is changes to annual rainfall volumes. Over the past few decades, the annual rainfall in Scotland has increased significantly, with this trend predicted to continue (Scotland's Environment, 2023). Water can be a major cause of damage to traditional properties, as it can penetrate the building fabric. This causese issues such as dampness, masonry damage and timber decay, in addition to providing sustenance to plant life, such as moss and ivy, which can cause further issues. Another potential problem linked to predicted weather changes and increased rainfall is increased humidity, which may cause building fabric elements to decay at an accelerated rate.

Through a combination of effective maintenance and retrofit interventions, it’s possible to ensure Scotland’s traditional buildings are better equipped to deal with the changing climate.

Chimneys

The highest part of a traditional roof structure is likely to be the chimney pots (if present). A simple alteration which can improve the ability of traditional properties to deal with rainwater is the installation of ventilated chimney cowls. Chimney cowls are a type of cap which attaches to the top of a chimney pot, providing a protective covering and preventing rainwater falling directly into the building via the flue. Chimney pointing & haunching also plays a role in the weather resistance of traditional buildings. Defective pot haunching, or defective pointing on the stack itself, may permit water ingress. Chimney pot haunching and stack pointing should be subject to regular inspections as part of a planned maintenance plan for the property.

Flashings

Roof flashings are also important building components, they direct water from the roof toward rainwater goods. Flashings are often formed from lead or zinc and are shaped to follow the lines of the roof structure, commonly being installed over junctions between roofing components, such as at ridges and valleys. Due to their exposed positioning, flashings can degrade over time, so they should be regularly inspected. To enhance the ability of a traditional building to shed rainwater, installing additional and more robust lead details can be considered, though this may have a significant visual impact and may require statutory consent.

Roof covering

The roof covering plays a vital role in shedding water from a traditional building. Many traditional properties have slate roofs. Whilst slate is a hardwearing material which can last for over a century, it can still suffer damage. Strong winds, nail sickness and broken slates are common issues which result in an incomplete roof covering, creating weak points through which water can enter the building and cause damage. To reduce the risk of such issues, it is important that roofs are regularly inspected and necessary repairs performed in a timely manner. Repairs to slate roofs should only be performed by competent roofing contractors and should be ‘like-for-like’, using slates of an appropriate type to match the existing roof covering, secured with non-ferrous nails to reduce the risk of future nail sickness.  

Rainwater Goods

Rainwater goods, such as gutters and downpipes, direct water away from the property and into the drainage system. To function effectively, it’s important that rainwater goods are in good condition and of sufficient size to deal with expected rainfall volumes. However, as rainfall volume in Scotland has, and will continue to, increase, some rainwater goods are unable to shed rainwater quickly enough, causing gutters to overflow and saturating masonry. Not only is saturated masonry at risk of structural damage, but damp materials also struggle to insulate buildings effectively, increasing heat loss from within properties. To ensure traditional buildings are best placed to deal with changing weather patterns, rainwater goods should be subject to regular inspection and maintenance. Simple tasks, such as clearing gutters on a bi-annual basis, can help to prevent issues, whilst in areas of severe rainfall, gutters or downpipes which are of a larger diameter may be installed, please note that this may require statutory consent. The ability of a traditional property to deal with increased rainfall may also be increased by altering masonry and leadwork details such as drips and string courses. These components help buildings to shed water away from their external walls, reducing the risk of water ingress or masonry saturation and associated problems.

Preventing Excess Humidity

To effectively control the moisture content of a building’s interior buildings must have sufficient ventilation. Many traditional properties rely upon having a vapour-permeable building envelope to ensure they can effectively regulate their internal moisture levels. To maintain adequate levels of ventilation, it’s important to ensure that original features such as solum vents are well maintained and that modern alterations to the building fabric do not compromise the breathability of the building. Certain modern insulation materials installed to improve energy efficiency are not particularly vapour permeable, which can result in the ventilation within a traditional property being compromised. Therefore, when installing insulation within a traditional property it is important to ensure that vapour permeable materials are used. Additional retrofit solutions for improving ventilation include installing ventilation grilles to sash and case windows, installing additional wall vents, fitting roof vents and replacing roofing felts which are not breathable when undertaking larger re-slating works. Dehumidifiers and disposable moisture traps may also help to regulate internal moisture levels, helping traditional buildings cope with the effects of Scotland’s changing climate.

Supporting you to love your building

By owning and caring for your traditional property, you are helping to protect it for the future, preserving Stirling’s nationally significant historic environment. Looking after an older property is not simple, tackling repairs can be a daunting task, which is why the not-for-profit Traditional Buildings Health Check scheme was set up.

We are here to help you look after your property, assisting you with diagnosing problems, planning the next steps in maintaining your building and applying for grant funding.

Find out more

Read our other Retrofit Blogs

• Retrofitting Traditional Buildings
• Retrofitting Traditional Buildings: Fabric First
• Retrofitting Traditional Buildings: Windows
• Retrofitting Traditional Buildings: Insulation
• Retrofitting Traditional Buildings: Chimneys

Further Information

Further Information relating to climate change, and the adaptation of traditional Scottish properties to deal with Scotland’s changing climate can be found at the following links:

• Historic Environment Scotland – A Guide To Climate Change Impacts 
• Historic Environment Scotland - Short Guide: Climate Change Adaptation for Traditional Buildings

Retrofitting Traditional Buildings

The first blog in our new TBHC Retrofit series takes a look at why the Retrofitting of Traditional Buildings is necessary.

Retrofitting Traditional Buildings: Fabric First

In our second blog in our TBHC Retrofit series Callum, SCHT Heritage Trainee, takes a look at the Fabric First approach to retrofit and why it is important.

Retrofitting Traditional Buildings: Windows

In our third blog in our TBHC Retrofit series, Callum, SCHT Heritage Trainee, takes a look at retrofit solutions for sash and case windows.

UK Shared Prosperity Fund

The UK Shared Prosperity Fund is a central pillar of the UK government’s Levelling Up agenda and provides £2.6 billion of funding for local investment by March 2025. The Fund aims to improve pride in place and increase life chances across the UK investing in communities and place, supporting local business, and people and skills. For more information, visit https://www.gov.uk/government/publications/uk-shared-prosperity-fund-prospectus