STONE MASONRY

Vineet Shrivastava
Associate Professor
Department of Planning & Architecture
Mizoram University
 Stone Masonry

 The construction of stones bonded together with mortar is termed as stone masonry where the stones
are available in a abundance in nature, on cutting and dressing to the proper shape, they provide an
economical material for the construction of various building components such as walls, columns,
footings, arches, lintels, beams etc.

Uses

1) Building foundations, walls, piers, pillars, and architectural works.

2) Lintels, Beams, beams Arches, domes etc.,
3) Roofs and Roof coverings.
4) Cladding Works
5) Dams, light houses, monumental structures.
6) Paving jobs
7) Railway, ballast, black boards and electrical switch
 General Principles

 The stones to be used for stone masonry should be hard, tough and durable.

 The pressure acting on stones should be vertical.

 The stones should be perfectly dressed as per the requirements.

 The mortar to be used should be good quality and in the specified faces.

 The construction work of stone masonry should be raised uniformly.

 The plumb bob should be used to check the verticality of erected wall.
 As far as possible broken stones or small stones chips should not be used.

 Double scaffolding should be used for working at higher level.

 The masonry hearting should be properly packed with mortar and chips if necessary to avoid hallows.

 The properly wetted stones should be used to avoid mortar moisture being sucked.

 The masonry work should be properly cured after the completion of work, for a period of 2 to 3
weeks.

 In order to obtain uniform distribution of load, under the ends of girders, roof trusses etc large flat
stones should be used
 Laying The Stone

 Decrease the stone thickness from the bottom to the top of wall.

 Ensure that headers in “walls of 2 feet (600 mm) or less in thickness” extend entirely through the wall. The
headers shall occupy at least 20 percent of the face of the wall.

 Lay the masonry in roughly levelled courses. Ensure that the bottom of the foundation is large, with
selected stones.

 Regularly diminish the thicknesses of the courses, if varied, from the bottom to the top of the wall. Keep a
surplus supply of stones at the site to select from.

 Before laying the stone in the wall, shape and dress it so that it will not loosen after it is placed. No
dressing or hammering which will loosen the stone will be permitted after it is placed.

 Clean each stone and saturate it with water before setting it. Clean and moisten the bed that will receive it.

 Bed the stones in freshly made mortar with full joints. Carefully settle the stones in place before the mortar
sets.

 Ensure that the joints and beds have an average thickness of not more than 1 inch. (25 mm).

 Ensure that the vertical joints in each course break with the adjoining courses at least 6 in. (150 mm).
 If a stone is moved or if the joint is broken after the mortar has set, take the stone up and
thoroughly clean the mortar from the bed and joints. Reset the stone in fresh mortar.

 NOTE: Do not lay the masonry in freezing weather or when the stone contains
frost, except with permission subjected to the required conditions.

 Whenever possible, properly point the face joints before the mortar sets. If joints cannot be
pointed, rake them out to a depth of 1 in (25 mm) before the mortar sets.

 Thoroughly wet the joints pointed after the stone is laid with clean water and fill with
mortar.

 Drive the mortar into the joints and finish with an approved pointing tool.

 Keep the wall wet while pointing. In hot or dry weather, protect the pointed masonry from
the sun and keep it wet for at least three days after the pointing is finished.

 NOTE: Do not perform pointing in freezing weather or when the stone contains
frost.

 After the pointing is completed and the mortar is set, thoroughly clean the walls and leave
them in a neat condition.
 Types of Stone Masonry:
Based on the arrangement of the stone in the construction and degree of refinement
in the surface finish, the stone masonry can be classified broadly in the following
two categories

1. Rubble Masonry

2. Ashlar Masonry

1) Rubble Masonry:

In this category, the stones used are either undressed or roughly

dressed having wider joints. This can be further subdivided as un-
coursed, coursed, random, dry, polygonal etc.

 Un-coursed Rubble Masonry:

This is the cheapest, roughest and poorest form

of stone masonry. The stones used in this type
of masonry very much vary in their shape and size
and are directly obtained from quarry. Un-coursed
rubble masonry can be divided into the following.

a) Un-coursed random rubble

b) Un-coursed squared rubble
 Uncoursed Rubble asonry

 Un-coursed Random Rubble Masonry:

The weak corners and edges are removed with mason’s hammer. Generally, bigger stone
blocks are employed at quoins and jambs to increase thes strength of masonry.
Un-coursed Rubble Masonry

 Un-coursed Squared Rubble

In this type thes Stone blocks are made

roughly square with hammer. Generally
the facing stones are given hammer-
dressed finish. Large stones are used as
quoins. As far as possible the use of chips
in bedding is avoided
Regular Course
 Polygonal Rubble Masonry:

In this type of masonry the stones are

roughly dressed to an irregular
polygonal shape. The stones should be
so arranged as to avoid long vertical
joints in face work and to break joints as
much as possible. Small stone chips
should not be used to support the
stones on the facing as shown in the
figure

below.
 Flint Rubble Masonry:

This type of masonry is used in the areas where the flint is available in plenty.
 Dry Rubble Masonry

This type of masonry is used in the construction of retaining walls, pitching earthen
dams and canal slopes in the form of random rubble masonry without any mortar. The
hollow spaces left around and stone should be tightly packed with smaller stone pieces
as shown

This may be used for non-load bearing walls such as compound walls, etc…
 Ashlar Masonry

 This type of masonry is built from accurately dressed stones with uniform and fine joints
of about 3mm thickness by arranging the stone blocks in various patterns.

In this masonry are the courses are of uniform height, all the joints are regular, thin and
have uniform thickness. This type of masonry is much costly as it requires dressing of
stones. The size of stones blocks should be in proportion to wall thickness.

In this type Ashlar masonry, each stone is cut to uniform size and shape with all sides
rectangular, so that the stone gives perfectly horizontal and vertical joints with adjoining
stone.

The various types of masonry can be classified

under the following categories are

1) Ashlar Fine
2) Ashlar Rough tooled Masonry
3) Ashlar Rock or Quarry faced
4) Ashlar facing
5) Ashlar Chamfered Masonry
6) Ashlar block in course
 Ashlar Masonry

Ashlar Fine or Coursed Ashlar Masonry:

In this type of stone masonry stone blocks of same height in each course are used. Every stone is fine
tooled on all sides. Thickness of mortar is uniform through out. It is an expensive type of stone masonry
as it requires heavy labour and wastage of material while dressing. Satisfactory bond can be obtained in
this type of stone masonry.

Ashlar fine Ashlar rough

 Ashlar Masonry

In this type of Ashlar masonry, a strip about 25mm wide and made by means of chisel is provided
around the perimeter of every stone as in case of rough-tooled Ashlor masonry. But the remaining
portion of the face is left in the same form as received from quarry.

Ashlar rock or quarry faced Ashlar block in course

 Ashlar Masonry

In this type of Ashlar masonry, the strip is provided as below. But it is chamfered or
bevelled at an angle of 45 degrees by means of chisel for a depth of about 25mm
Ashlar chamfered

Facing

Ashlar facing
This is combination of rubble masonry and Ashlar
masonry. In this type of masonry, the face work is
provided with rough tooled or hammer dresses
stones and backing of the wall may be made in
rubble masonry.
Ashlar rough tooled masonry

In this type of Ashlar masonry, the beds and sides are finely chisel-dressed. But the face
is made rough by means of tools. A strip, about 25mm wide and made by means of
chisel is provided around the perimeter of the rough dressed face of each stone.
 Cornice

 A Cornice
is generally any horizontal decorative molding that crowns a building or furniture element— the
cornice over a door or window, for instance, or the cornice around the top edge of a pedestal or
along the top of an interior wall.

 The function of the projecting cornice of a building is to throw rainwater free of the building’s walls.
SILLS

Sloped Outer
REVEAL

Stone Sill
 Rubble
Masonry
Wall

Chamfered
Quoins

Stone Sill

Edge Drop
Min 25Cm Overlap
into the abutting
masonry
Sill as a Ledge
in the Interior
PLINTHS
Traditional Plinth
Plinth in Random Rubble Masonry to receive A Load-Bearing wall Above.
Plinth Platform Conventional Plinth in Rural Areas
Thank You