What Is Ashlar Stone Masonry?
What Is Ashlar Stone Masonry?
Ashlar masonry is a type of stone masonry that is formed using finely dressed stones of the same size, shape, and texture laid together in cement or lime mortar of equal size joints at right angles to each other.
The stones used in ashlar masonry are usually rectangular cuboid blocks, and the joints between the stones are very thin, regular, and of uniform thickness. Ashlar masonry is in contrast to rubble masonry, which employs irregularly shaped stones.
Ashlar masonry may be divided into several categories including Ashlar Fine Tooled Masonry, Ashlar Rough Tooled Masonry (Bastard Ashlar), Ashlar Rock or Quarry Faced, Ashlar Chamfered Masonry, Ashlar Block in Course, and Random Rubble Masonry.
In ashlar fine tooled masonry, the beds and sides of each stone block are finely chisels dressed just in the same manner as for ashlar fine. In ashlar rough tooled masonry, the exposed face is dressed by rough tooling.
In ashlar rock or quarry-faced masonry, the exposed faces of the stones are left rough. In ashlar chamfered masonry, a strip around the perimeter of the exposed face is chamfered at an angle of 45° to a depth of 25 mm.
In ashlar block in course masonry, the faces of each stone are hammer dressed but the vertical joints are not as straight and fine as in ashlar fine tooled. Finally, random rubble masonry involves randomly placed stones with no specific pattern.
Ashlar masonry has been used in many buildings as an alternative to brick or other materials, and it has been used to give buildings an exposed and good aesthetics.
What Is An Example Of Ashlar Masonry?
Examples of ashlar masonry have been found on pyramids in ancient Egypt and on structures in classical Greece. In Incan architecture, ashlar masonry is the term given to the finely beveled rocks fitted closely next to one another.
The pyramids found alongside stone monuments in Hidalgo, Mexico is examples of Pre-Columbian architecture which employed ashlar masonry.
Ancient Egyptian architecture also used ashlar masonry as a building technique, with mud brick and stone being the two principal building materials used.
What Are The Three Types Of Stone Masonry?
The three types of stone masonry are ashlar chamfered masonry, ashlar rough tooled masonry, and rock or quarry-faced masonry.
Ashlar chamfered masonry is a special type of ashlar rock-faced in which the strip provided around the perimeter of the exposed face is chamfered at an angle of 45° to a depth of 25 mm.
Ashlar rough-tooled masonry consists of stones with faces that are roughly tooled and dressed with chisels.
Rock or quarry-faced masonry is similar to rough tooled ashlar masonry, except that there is a chisel-drafted margin left rough on the face.
What Are The Specifications Of Ashlar Masonry?
The specifications of ashlar masonry require that the stones used should be small enough to be lifted and placed by hand.
The length of the stone shall not exceed three times the height, and the breadth on the base shall not be greater than three-fourths of the thickness of the wall, or not less than 15 cm. The height of the stones may be up to 30 cm.
The joints between the stones should be thin, regular, and of uniform thickness. Additionally, at least one-third of the stones should tail into the work for a length not less than twice their height.
The hearting or interior filling of the wall should consist of stones carefully selected to ensure that they do not exceed 15% of the quantity of stone masonry and stone in each course. Finally, no more than two stones should be used at a course’s height.