Stones

Stones in Architecture and their method of construction

            Stone had been used as a type of building material since thousands of years ago. It is well-known and widely recognized by its properties of having great durability and superior artistic quality as well as natural textures, thus becoming the primary choice of building material for building associated with status, power and religion. Below are a few examples of architecture design using stone:

            In dealing with stones, basically there are 2 types of construction methods, which is the dry stone stacking method and stone masonry.

Dry stone stacking:

            This method is also known as dry stacking, which is the earliest form of stone construction. In this method, irregularly shaped stones are carefully selected and placed so that they fit closely together without slipping, as in freestanding structures such as bridges and buildings. Structures are typically wider at the base and taper in as height increases.  In terms of structural stability, the weight of the stone will pushes inwards to support the structure, and any settling or disturbance will causes the structure to lock together and become even stronger. The structures constructed through this method are highly durable and easy for maintenance.  This method of construction does also allow water to pass through without damaging the stones.

Stone masonry :

            This method is actually an evolution of the dry stone stacking method. Stone blocks are laid in rows of even (course) or uneven (uncourse) height, and fixed in place with mortar, a cement or lime mixture pasted between the stones. Unlike the dry stacking method, the stones used in this method actually undergo some processes before being used. The stones usually are extracted by surface quarrying, drilled and split using diamond saws or iron wedges, and then shaped and polished according to their requirements. Basic hand tools such as chisels, mallet and a metal straight edge are used to shape the stones, but in considering about the money and time, modern power tools such as angle grinders and compressed air-chisels are usually used. Stones are either shaped (dressed) into a block, known as ashlar masonry, or left rough and cut irregularly, known as rubble masonry. However, this method of construction is not so durable as compare to dry stone because the mortar used will cause water to get trapped between the stones and push them apart.

            Nowadays, traditional stone masonry is rarely used due to the expensive cost to quarry, cut and transport, and the construction process is skill-intensive. Instead, most modern stonework utilises a veneer of stone (thin, flat pieces) glued against a wall of concrete blocks. This is known as veneered stone or stone cladding.

            In a cross between veneered masonry and traditional masonry, the slipform stone structures are constructed by placing short forms (around 2 feet tall) on either side of the wall, to serve as a guide for the structure. Next, the stones are placed inside the forms with the flat face out, followed by pouring the concrete behind the stones to hold them together. Through this way, stone buildings can be constructed quickly and easily.