Mark Folkes | Heritage Lime

Lime Buildings and Structures in the UK!

by Mark Folkes | Jul 8, 2023 | Blog, Historic & Traditional Skills, Stonemasonry

Lime is the principal binder of most traditional mortars, plasters and renders, with it central to the successful maintenance and repair of traditional buildings and their fabric. An understanding of lime is essential for anyone working on historic buildings and construction in general.

The history of lime being used for building in Britain is a long one, with the romans employing it in their construction. This has been continued to be used today, with lime regarded as one of the most ecological and environmentally friendly sources when it comes to construction.

In order to gain a feel for just how efficient lime products are in Britain, here are some monuments and attractions that used lime materials in their construction.

The Pontcysyllte Aqueduct

Known as the ‘stream in the sky’, the Pontcysyllte Aqueduct is a navigable aqueduct that carries the Llangollen Canal across the River Dee in the Vale of Llangollen in northeast Wales. Completed in 1805, it is used for narrowboat transportation, having been a key part of the central section of the proposed Ellesmere Canal, an industrial waterway that would have created a commercial link between the River Severn at Shrewsbury and the Port of Liverpool on the River Mersey.

Built by civil engineer Thomas Telford, the aqueduct is 12 ft (3.7 metres) wide and is the longest aqueduct in Great Britain (307 metres) and the highest canal aqueduct in the world. You can walk, cycle or boat across the aqueduct, only a mere 125 feet in the air! The mortar used by Telford to compromise the stones of the aqueduct was made from lime, water and ox blood. Due to its rich history and interesting manor, the landmark is classed as a World Heritage Site. A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO).

Eddystone Lighthouse

The Eddystone Lighthouse lies on the Eddystone Rocks in southeast Cornwall, 13 miles southwest of the small-port city of Plymouth. The interior of the construction uses limestone masonry, with the rocks supporting the lighthouse itself submerged below sea level. Located in some of the harshest weather conditions in the country, the need for the lighthouse came due to mariners not being able to see the rocks, causing multiple shipwrecks locally.

Being the fourth of its kind, the structure has remained since 1882. The first lighthouse (Winstanley’s) was swept away in a powerful storm, killing its architect and five men in the process. The second (Rudyard’s) stood for fifty years before it burned down. The third (Smeaton’s) is the best known, renowned because of its influence on lighthouse design and its importance in the development of concrete for building; its upper portions were re-erected in Plymouth as a monument. The first lighthouse, completed in 1699, was the world’s first open ocean lighthouse.

The strength of the structure is very impressive, with it being able to withstand even the worst of storms, even after being moved, block by block, in the 19th century, making it one of the most infamous lighthouses not only in the UK, but in the world.

Conwy Castle

Constructed by Edward I during the conquest of Wales between 1283 and 1289, the Conwy Castle is located in Conwy, North Wales. Over the next few centuries, the fortification played an important part in several wars, including acting as a temporary haven for Richard II in 1399. Following the outbreak of the English Civil War in 1642, the castle was held by forces loyal to Charles I, holding out until 1646 when it surrendered to the Parliamentary armies. Likewise, to the Pontcysyllte Aqueduct, it is known as a World Heritage Site.

The castle is defended by eight large towers and two barbicans, with a postern gate leading down to the river, allowing the castle to be resupplied from the sea. It retains the earliest surviving stone machicolations in Britain. The castle sits on a coastal ridge of limestone and grey sandstone. Much of the material of the castle was taken from the ridge itself, but some sources of sandstone were brought in from neighbouring cities and towns.

These are just three examples of the hundreds of sites that contain lime-based products in their construction in the UK, let alone worldwide! The efficiency and long-lasting life of lime in buildings has continued to pass the test the time, even in some of the most dangerous conditions.

3 Key Benefits To Using Lime (mortars and renders)!

by Mark Folkes | Jul 8, 2023 | Blog, Lime Products, Services

In the world of construction, lime has been used as a primary ingredient for centuries, with it continuously used in the present day for both historical and contemporary applications. Used for a variety of benefits, lime is a major constituent in exterior and interior structures and plasters, enhancing the strength, durability, and workability of these finishes. Whilst lime can be used for building conservation and renovation, it is also becoming a popular choice for new builds due to its superior aesthetic properties that it possesses. Used in mortar, render, plaster, putty and more, builders across Britain are rapidly upgrading their materials to lime products to gain the best results possible, whilst also staying environmental and cost friendly. Let’s have a look at some of the key benefits to switching to lime-based products today!

Reduced Cracking and Movement

Incorporating lime in your projects will help the construction withstand the minor movements that occur naturally inside the sedimentary (thermal expansion, contraction, erosion…etc). These movements and changes can cause products to develop large cracks or to ‘debond’ from the substrate, often damaging the substrate. Incorporating hydrated lime into the mixture encourages crack formation to be in the form of gradual ‘micro-cracking’ within the material, rather than large cracking which can appear on the outside of the material over time. These micro-cracks therefore repair themselves naturally by a process of hydrated lime diffusing into these tiny fissures created naturally and then hardening by reacting with atmospheric carbon dioxide to form calcium carbonate (limestone). This process is commonly known as ‘autogenous healing’, the process of concrete to repair in the presence of moisture (our lime products). This will ensure your project and the materials used will be sturdy and strong for a prolonged period, whilst also continuing to look aesthetically pleasing with the reduced amount of natural cracking and movement.

Ecologically and environmentally friendly

Lime has less embodied energy than cement
Free lime absorbs carbon dioxide in the setting process of carbonation
Lime is produced on a small and cost-efficient scale
The gentle binding properties of lime enable full re-use of other materials
Small quantities of lime can protect otherwise vulnerable, very low energy materials
Using less embodied energy than cement with the benefit that it can be produced on a small scale
Can survive harsh weather conditions, so the environment will not be damaged through collapsing construction

Moisture movement, frost resistance and durability

The improved quality of the bond, and absence of large (or small) cracks, which comes from incorporating hydrated lime helps to reduce the risk of water ingress. This is when water infiltrates your project unknowingly. This term can also be used to describe the penetrating damp that can permeate some properties. Common signs that you have water ingress in your project is the development of mould and damp patches. However, mixtures containing appropriate proportions of hydrated lime have the ability to transmit water vapour (vapour permeability) than cement-only mixtures. This helps to stabilise the internal humidity of a building by absorbing and releasing moisture. This makes for a more comfortable environment and reduces surface condensation. This helps moisture to dissipate, allowing the structure to ‘breathe’ accordingly, therefore reducing any risk of frost damage due to saturation. Once again, this maintains the durability of the rock. So much in fact that even Caesar’s Tower at Warwick Castle has stood the test of time for over 600 years, with many cathedrals across the country and worldwide standing significantly longer. An outstanding example is the Pantheon Temple in Rome which has a lime concrete dome spanning over 43 metres (142 feet). This has survived for nearly 2000 years!

These are just some of the many benefits of using our range of lime products we have in stock. Lime-based products are easy to work with, remaining smooth and malleable, and they give a beautiful finish that develops a rich patina over time. Why not try it today? Check out our range of products now!