KNOWLEDGE HUB

Ashlar: Architectural Stonemasonry Explained

Jun 26, 2024

Ashlar is a term used in architectural stonemasonry to describe finely dressed stone blocks, typically cuboid, that are arranged in regular patterns to create a smooth, uniform surface. The term originates from the Latin word ‘axilla’, meaning ‘a small wing’, and has been used in construction for thousands of years, from the ancient pyramids of Egypt to the grand cathedrals of Europe.

The use of ashlar masonry is highly regarded for its aesthetic appeal and structural integrity. It requires a high level of skill and craftsmanship to produce, and as such, is often associated with prestigious and high-quality construction. In this comprehensive glossary entry, we will delve into the intricacies of ashlar masonry, exploring its history, types, techniques, and applications in architectural design.

History of Ashlar Masonry

The history of ashlar masonry is as old as civilisation itself. The earliest examples can be traced back to the ancient Egyptians, who used large, finely cut stones to build their monumental pyramids and temples. The Greeks and Romans also utilised ashlar masonry in their architecture, with the Parthenon in Athens and the Colosseum in Rome standing as testaments to their mastery of the craft.

During the Middle Ages, ashlar masonry became a hallmark of ecclesiastical architecture. Cathedrals, churches, and monasteries across Europe were constructed using ashlar blocks, showcasing the intricate detailing and precision that the technique allows. The Renaissance period saw a revival of classical architectural principles, and with it, a renewed interest in ashlar masonry. This trend continued into the modern era, with ashlar being used in a variety of architectural styles, from Neoclassical to Art Deco.

The Ancient World

In ancient Egypt, ashlar masonry was used to construct the pyramids, the largest and most famous of which is the Great Pyramid of Giza. This colossal structure, built around 2600 BC, is made up of over 2 million ashlar blocks, each weighing an average of 2.5 tons. The precision with which these blocks were cut and arranged is a testament to the skill and ingenuity of the ancient Egyptian builders.

The Greeks and Romans also made extensive use of ashlar masonry. The Parthenon, built in the 5th century BC, is a prime example of Greek ashlar construction. Its Doric columns, made from marble ashlar blocks, are renowned for their symmetry and proportion. The Romans, too, utilised ashlar masonry in their architecture, most notably in the construction of the Colosseum, a massive amphitheater built in the 1st century AD.

The Middle Ages and Renaissance

During the Middle Ages, ashlar masonry was predominantly used in the construction of religious buildings. Gothic cathedrals, such as the Notre-Dame in Paris and the Canterbury Cathedral in England, feature extensive use of ashlar in their walls, towers, and buttresses. The precision and uniformity of ashlar masonry allowed for the creation of intricate designs and patterns, contributing to the ornate and grandiose style of Gothic architecture.

The Renaissance period saw a revival of classical architectural principles, and with it, a renewed interest in ashlar masonry. Buildings from this era, such as the Palazzo Medici Riccardi in Florence and the Château de Chambord in France, showcase the elegance and sophistication of ashlar construction. The blocks were often cut with such precision that they could be fitted together without the use of mortar, a technique known as ‘dry-stone’ masonry.

Types of Ashlar Masonry

Ashlar masonry can be categorised into several types, based on the finish of the stone blocks and the way they are laid. These include random ashlar, coursed ashlar, and chamfered ashlar, among others. Each type has its own unique characteristics and applications, and can greatly influence the aesthetic and structural qualities of a building.

Section Image

Random ashlar, as the name suggests, involves the use of stone blocks of varying sizes and shapes. The blocks are fitted together in a seemingly random pattern, creating a rustic and natural appearance. Coursed ashlar, on the other hand, involves the use of uniformly sized blocks that are laid in horizontal courses or layers. This results in a more formal and structured appearance. Chamfered ashlar involves the use of blocks that have been beveled or chamfered at the edges, creating a distinctive pattern of lines and shadows on the surface of the wall.

Random Ashlar

Random ashlar is a type of ashlar masonry that uses stone blocks of varying sizes and shapes. The blocks are fitted together in a seemingly random pattern, creating a rustic and natural appearance. This type of ashlar is often used in country houses and cottages, where it blends seamlessly with the natural surroundings. Despite its seemingly haphazard arrangement, random ashlar requires a high level of skill and craftsmanship to execute effectively.

The key to successful random ashlar construction lies in the careful selection and placement of the stone blocks. Each block must be chosen for its size, shape, and colour, and then meticulously fitted together with the others to create a harmonious and balanced composition. The result is a wall that is not only structurally sound, but also visually appealing, with a unique texture and character that sets it apart from other types of masonry.

Coursed Ashlar

Coursed ashlar is a type of ashlar masonry that uses uniformly sized blocks that are laid in horizontal courses or layers. This results in a more formal and structured appearance, with a clear rhythm and pattern to the arrangement of the blocks. Coursed ashlar is often used in public buildings, such as town halls and libraries, where it conveys a sense of order and stability.

The construction of coursed ashlar requires a high level of precision and consistency. Each block must be cut to the exact same size and shape, and then laid in perfect alignment with the others. The joints between the blocks must also be carefully managed, to ensure that they are evenly spaced and filled with the right amount of mortar. The result is a wall that is not only structurally robust, but also visually striking, with a clean, geometric aesthetic that is both timeless and modern.

Chamfered Ashlar

Chamfered ashlar is a type of ashlar masonry that uses blocks that have been beveled or chamfered at the edges. This creates a distinctive pattern of lines and shadows on the surface of the wall, adding depth and dimension to the overall design. Chamfered ashlar is often used in contemporary architecture, where it provides a modern and sophisticated aesthetic.

The process of chamfering involves cutting away the edges of the stone blocks at an angle, to create a sloping or beveled edge. This can be done by hand, using a chisel and mallet, or by machine, using a stone-cutting saw. The degree of chamfering can be varied, from a subtle bevel to a more pronounced slope, depending on the desired effect. The result is a wall that is not only visually interesting, but also tactile and engaging, inviting the viewer to touch and explore its surface.

Techniques of Ashlar Masonry

The construction of ashlar masonry involves a number of specialised techniques, from the cutting and dressing of the stone blocks, to their placement and bonding. These techniques require a high level of skill and craftsmanship, and are often passed down from generation to generation, preserving the traditional methods of stonemasonry.

The first step in ashlar construction is the quarrying of the stone. This involves the extraction of large blocks of stone from a quarry, using a variety of tools and techniques. Once the stone has been quarried, it is then cut and dressed into the desired shape and size. This is a meticulous process, requiring a keen eye for detail and a steady hand. The blocks are then laid in a predetermined pattern, with each block carefully aligned and bonded with the others. The joints between the blocks are then filled with mortar, to secure them in place and prevent water ingress.

Quarrying

The quarrying of stone for ashlar masonry is a complex and labor-intensive process. It involves the extraction of large blocks of stone from a quarry, using a variety of tools and techniques. These may include drilling, blasting, wedging, and levering, depending on the type of stone and the conditions of the quarry.

Once the stone has been extracted, it is then transported to the workshop or construction site, where it will be cut and dressed. The size and weight of the stone blocks can make this a challenging task, requiring the use of heavy machinery and specialised equipment. Despite these challenges, the quarrying of stone is a crucial step in the ashlar construction process, providing the raw material for the mason’s craft.

Cutting and Dressing

The cutting and dressing of stone is a key part of the ashlar construction process. This involves shaping the quarried stone into the desired size and shape, using a variety of tools and techniques. The stone may be cut using a saw, chisel, or other cutting tool, depending on the type of stone and the desired finish. The edges of the stone are then dressed, or smoothed, using a mallet and chisel. This gives the stone its final shape and surface texture, ready for placement in the wall.

The process of cutting and dressing stone requires a high level of skill and precision. Each block must be cut to the exact dimensions specified in the design, with a tolerance of just a few millimetres. The edges must be dressed to a smooth and even finish, ensuring that the blocks fit together perfectly. This meticulous attention to detail is what sets ashlar masonry apart from other types of construction, and is a testament to the skill and craftsmanship of the stonemason.

Placement and Bonding

The placement and bonding of the stone blocks is the final stage in the ashlar construction process. This involves arranging the blocks in a predetermined pattern, with each block carefully aligned and bonded with the others. The blocks are typically laid in horizontal courses, with each course offset from the one below it, in a pattern known as ‘stretcher bond’. This provides stability and strength to the wall, preventing it from collapsing under its own weight.

The joints between the blocks are then filled with mortar, a mixture of sand, cement, and water. The mortar acts as a bonding agent, securing the blocks in place and preventing water ingress. The joints must be carefully managed, to ensure that they are evenly spaced and filled with the right amount of mortar. Once the mortar has set, the wall is then cleaned and finished, ready for its final inspection. The result is a wall of exceptional quality and beauty, a true testament to the art of ashlar masonry.

Applications of Ashlar Masonry

Ashlar masonry has a wide range of applications in architectural design, from residential buildings to public monuments. Its versatility and aesthetic appeal make it a popular choice for architects and designers, who use it to create structures of enduring beauty and strength.

In residential architecture, ashlar is often used in the construction of exterior walls, where it provides a durable and weather-resistant surface. Its natural beauty and texture add character and charm to the home, while its structural integrity ensures long-lasting performance. In public architecture, ashlar is used in the construction of civic buildings, such as town halls, libraries, and museums. Its formal and dignified appearance conveys a sense of stability and permanence, reflecting the important role these buildings play in the community.

Residential Architecture

In residential architecture, ashlar masonry is often used in the construction of exterior walls. Its natural beauty and texture add character and charm to the home, creating a warm and welcoming atmosphere. The durability and weather-resistance of ashlar make it an ideal choice for exterior applications, where it can withstand the elements and maintain its appearance over time.

Ashlar can be used in a variety of architectural styles, from traditional to contemporary. In traditional homes, it can be used to create a rustic and homely aesthetic, with its natural colours and textures blending seamlessly with the surrounding landscape. In contemporary homes, it can be used to create a sleek and modern aesthetic, with its clean lines and geometric patterns providing a striking contrast to the organic forms of nature.

Public Architecture

In public architecture, ashlar masonry is used in the construction of civic buildings, such as town halls, libraries, and museums. Its formal and dignified appearance conveys a sense of stability and permanence, reflecting the important role these buildings play in the community. The precision and uniformity of ashlar construction also lend themselves well to the grand and monumental scale of these buildings, creating a powerful and imposing presence.

Ashlar can also be used in the construction of public monuments and memorials, where it provides a fitting tribute to the individuals or events being commemorated. Its durability and resistance to weathering ensure that these monuments will stand the test of time, preserving the memory of the past for future generations.

Conclusion

In conclusion, ashlar masonry is a time-honoured technique that has been used in construction for thousands of years. Its enduring popularity is a testament to its aesthetic appeal and structural integrity, which make it a versatile and reliable choice for a wide range of architectural applications. Whether used in the construction of a humble cottage or a grand cathedral, ashlar masonry embodies the skill and craftsmanship of the stonemason, creating structures of enduring beauty and strength.

As we continue to explore new materials and technologies in the field of architecture, it is important to remember the traditional techniques that have served us so well in the past. Ashlar masonry is one such technique, a testament to the timeless appeal of natural stone and the skill of the craftsman. As we look to the future, we can take inspiration from this ancient craft, applying its principles of precision, craftsmanship, and beauty to our own designs.

Discover the Craftsmanship of AF Jones Stonemasons

Embrace the legacy of ashlar masonry with the expertise of AF Jones Stonemasons. With over 160 years of heritage and a blend of traditional skills and modern technology, we stand ready to bring your architectural vision to life. From grand designs to bespoke details, our in-house team in Oxfordshire & Berkshire delivers excellence across the south of England and London. Experience our comprehensive service, from concept to installation, and let us demonstrate the true potential of stone in your next project. For a seamless journey in realising your architectural aspirations, we invite you to make an enquiry and explore the possibilities with us.

Realise your project, guided by our architectural stonemasonry experts.