Stone masonry is a type of masonry, where natural rocks are cut and give them proper shape to make stones. These stones are used with mortar for the construction of foundations, walls, floors, and many other types of masonry work. Stones are one of the most durable and strong building materials.
Types of Stone Masonry
Stone masonry can be classified into the following two types:
- Rubble Masonry
- Ashlar Masonry
1. Rubble Masonry
The type of masonry, where raw, undressed, or roughly-dressed stones are laid with the mortar is called rubble masonry. Since they are almost raw and untouched, the stones have more varied shapes and sizes. In this masonry, the joints are not of uniform thickness.
Rubble masonry is further classified into the following three types:
- Random rubble masonry
- Squared rubble masonry
- Dry rubble masonry
1. Random rubble masonry
Random rubble masonry is the roughest type of stone masonry. Random rubble masonry can use un-dressed stone or hammer-dressed stone. The stones are properly chosen and installed to distribute the pressure over a large area while at the same time avoiding long vertical joints.
The stones used are quarried in such a process and of such sizes so that they can be lifted and placed by hand.
Further random rubble masonry is also divided into the following types,
- a) Un-coursed Random Rubble Masonry
- b) Coursed Random Rubble Masonry
a) Uncoursed Random Rubble Masonry
It is the roughest and cheapest form of stonewalling. Since stones are of different shapes and sizes, they are arranged with great care so as to distribute pressure over the maximum area and at the same time avoid long vertical joints. The courses are not maintained regularly in this method of construction.
Initially larger stones are laid first, joints are filled and flushed. The weak corners and edges of the stone are removed. Mostly large stones are used at corners and at jambs to increase the strength of the masonry.
b) Coursed Random Rubble Masonry
The coursed random rubble masonry in which stones are placed in layers of the same height is called coursed random rubble masonry. In this masonry, the stones are placed in quite level courses. Headers of one coursed height are laid at particular distances. The stones are shaped with a hammer.
2- Squared Rubble Masonry
The rubble masonry, in which the face of stones is squared on all joints and beds by hammer or chisel dressing prior to their laying, is called squared rubble masonry.
There are two types of squared rubble masonry.
- a) Coursed Square Rubble Masonry
- b) Uncoursed square rubble masonry
a) Coursed Square Rubble Masonry
This is a superior variety of rubble masonry. Stones having straight beds and sides are leveled up to form courses of different depth. In this type, the stones are laid in rows with defined horizontal joints. The stones are to be laid in courses of equal layers and the joints should also be uniform.
b) Uncoursed square rubble masonry
This type of stone is laid in a more random pattern without defined vertical or horizontal joints known as uncoursed square rubble masonry. It includes stones that are squared on all joints and beds by hammer dressing. All the stones to be laid are of various sizes.
3. Dry rubble masonry
One of the most common types of rubble masonry is dry rubble masonry. This is quite similar to the other two types other than no mortar is used. Masons work with carefully picked hammer-shaped or raw stones. They lay them in such a way to minimize large joints, specifically large vertical joints that can damage the wall.
This type of stone masonry is perfect for boundary walls and other similar structures.
2. Ashlar Masonry
It is the type of stone masonry in which finely shaped stones are placed in cement or lime mortar is called ashlars masonry. The stones used are trimmed and shaped to have specific height and surface sizes. This means that type of masonry have even more control over the size and place of horizontal and vertical joints.
This type of masonry is more expensive because stones require to be carefully cut and shaped that’ll be used. This masonry is used for large structures, architectural buildings, and abutments of bridges.
Ashlars masonry is further divided into the following types,
- Rough Tooled Ashlars Masonry
- Quarry or Rock Faced Ashlars Masonry
- Chamfered Ashlars Masonry
- Random Course Ashlars Masonry
- Ashlar Facing
- Block in Course Masonry
- Ashlars Fine Tooled Masonry
1. Rough Tooled Ashlars Masonry
Rough-tooled ashlar masonry uses stones that have the sides cut to a specific shape and angle. However, the face of the stones is left quite rough and is just somewhat shaped and improved with a chisel or hammer.
This provides you a traditional view of the outside however a sturdy wall that is simpler to construct because the stones are already cut and shaped to fit together easier.
2. Quarry or Rock Faced Ashlars Masonry
In quarry-faced ashlar masonry, the sides of the stone are carefully dressed to give it a particular shape, while the face is rough, raw, and basically is left the same from the quarry.
Unlike rough-tooled ashlar masonry, quarry-faced ashlar stone faces are entirely unblemished. This provides it a rough surface on the outside.
3. Chamfered Ashlars Masonry
Chamfered ashlar is one of the most enhanced types of stone masonry. The stones are carefully shaped into proper blocks.
The faces are also shaped to have a more smooth appearance and after that, a small bevel is included around the stone’s face. This produces a very enhanced appearance that resembles typical brickwork.
4. Random Course Ashlars Masonry
This type of ashlar masonry includes fine or coursed ashlar stone however the courses are of different thicknesses. Although it prevails to lay stones in such a way that creates specified vertical and horizontal joints and can also lay stones randomly without developing regular mortar joints.
5. Ashlar Facing
Ashlar facing is the best type of ashlars masonry. Ashlar facing masonry is quite similar to the previous technique. Rather than using rubble masonry as the main part of the wall and the ashlar facing works just like a facade on the outside and obtain the appearance of the stone.
6. Block in Course Masonry
Block in course masonry is a mixture of rubble and ashlar masonry. The face of the wall is used ashlar stones that are cut to a particular shape. The remaining wall’s structure behind the face is used in the rubble masonry method.
7. Fine Tooled Masonry
Fine-tooled masonry utilizes stones that are exactly cut to specific shapes and sizes. Because they fit together so well, the mortar joints can be very thin.
This type can be more costly due to extra time to precisely cut and fit the stones, but the completion result is an extremely strong and refined wall.