Rubble stone masonry is one of the oldest and most durable construction techniques, used extensively in residential, commercial, and infrastructure projects. This guide provides an in-depth look at rubble stone masonry, covering its types, construction methods, material estimation, and cost breakdown.

If you're involved in masonry work, civil engineering, or construction planning, this guide will help you understand how to efficiently estimate materials and labor costs for rubble stone masonry.

Stone masonry is a construction technique that involves arranging and bonding stones with mortar to create strong, long-lasting structures. Throughout history, stone masonry has been used in iconic structures such as the forts of Rajasthan and historical landmarks like Delhi’s Lotus Temple. Today, it remains a preferred choice for finishing walls, facades, and landscaping projects due to its durability and timeless aesthetic.

Additionally, it plays a key role in landscaping, with stone walls used for decorative purposes, such as garden walls, retaining walls, and pathways, offering both functionality and visual appeal. Stone offers exceptional resistance to weather, fire, and wear, making it a popular choice for building materials.

In today’s world, where sustainability and durability are key priorities in construction, stone masonry remains a highly relevant and reliable choice for builders and designers, ensuring both functionality and aesthetic appeal for years to come.

Now, let's explore the different types of stone masonry.

Types of Stone Masonry

Our primary focus in this blog is on rubble stone masonry, so we will be examining this method in detail from now onwards.

Rubble Masonry is a type of stone masonry where the stones used are generally irregularly shaped and roughly dressed, giving the structure a more rustic and unpolished appearance. It is one of the oldest and simplest forms of masonry construction. The stones are typically laid in mortar to bind them together, but the stones themselves don't have to be cut with great precision, as in ashlar masonry.

Here are the detailed instructions for constructing the rubble stone masonry.

Step1. Stone Selection: The first step in making rubble masonry is selecting the right stones. These stones can be obtained from quarries or collected from natural sources, and they are chosen based on their strength and size

Step2. Preparing the Mortar: The mortar used in rubble masonry can be made of cement, lime, or a mix of both, along with sand and water. The mortar acts as the binding agent, holding the stones in place.

Step3. Stone Placement: The stones are placed in layers. When building, some stones are placed randomly (uncoursed), while others may be arranged in a more organized fashion (coursed rubble). This technique results in a structure with a rustic, uneven look.

Step4. Filling the Gaps: Once the stones are laid, the gaps between them are filled with mortar. Sometimes, smaller stones are placed in the gaps to enhance the stability and minimize the voids.

Step5. Leveling: After the stones are in place, the surface is leveled to ensure the structure is stable. The mortar is then left to cure, allowing the stones to be firmly bound together.

Let's explore the different types of rubble masonry.

Description:

Uncoursed rubble masonry is a traditional form of stone construction where stones are laid without any regular arrangement or uniform courses. In this method, stones are typically unshaped and vary in size, shape, and texture, which are sourced from local quarries, fieldstone, or natural rock formations. 

The lack of uniformity in stone placement gives the masonry a rustic, natural appearance. The stones are stacked randomly with joints that are often irregular in thickness, typically ranging from 10mm to 15mm. Large stones are usually placed at the corners to provide additional strength and stability, and any projecting corners are often knocked off to ensure better bonding between stones. 

A critical feature of uncoursed rubble masonry is the use of bond stones (through stones), which extend through the entire thickness of the wall, creating a continuous connection that enhances the wall's stability.

Materials Estimation:

The following assumptions are made: 

1. Cement Mortar mix of 1: 6 (1 cement : 6 coarse sand) is considered.
2. The volume of dry mortar is considered to be 40% of the volume of stone masonry.

For material estimation in uncoursed rubble masonry following steps to be followed:

Step 1: Estimation of Stone Masonry Quantity

The total volume of stone masonry is 10 m³, and with 25% additional wastage:   

Total Volume of Rubble Stone (with wastage) =10 m³ × 1.25 = 12.5 m³

Given the total volume of stone masonry is 12.5 m³ and the air gaps taken up by mortar reduce the volume, we can assume around 30-40% of the masonry volume is mortar, leaving about 60-70% as stone, so the average factor to account for calculation of stone masonry is considered to be 0.65.

Volume of rubble stone = 12.5 m³ x 0.65 = 8.125 m³

Step 2: Estimation of Mortar Quantity

The volume of dry mortar is 40% of the volume of stone masonry (not including wastage): Volume of Dry Mortar =10 m³ × 40% = 4 m³

Step 3: Estimation of Cement and Sand Quantities

In the mortar mix of 1: 6 (cement : sand), the total parts = 1+6 = 7 parts. So, the proportion of cement and sand by volume are: Cement = 1/7​ of total mortar volume. Sand = 6/7​ of total mortar volume.

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Cement Volume = 1/7 × 4 m³ = 0.571 m³                                                                       

Cement Volume = 0.571 x 1.02 = 0.582 m³ (adding 2% wastage)

Density of cement (1440 kg/ m³)

No. of bags of cement (each of 50 kg) = 0.582 x 1440 / 50 = 17 bags of cement

Sand Volume = 6/7 × 4 m³ = 3.429 m³                                                                              

Sand Volume = 3.429 x 1.05 = 3.6 m³ (adding 5% wastage)

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Cost Analysis:

Using material quantities obtained from the previous step, we will do the cost analysis. Here the rate considered for materials & labour cost is taken from CPWD DSR 2023. Also, the below table mentions rates of masonry work in substructure as well as superstructure.

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General Use:

This is often used in low-cost construction, where budget is a concern and aesthetics are secondary.

Description:

‍Coursed rubble masonry is a type of stone construction where stones are laid in regular horizontal layers, or courses, with each layer having stones of similar height. The height of each leveled course typically ranges from 300 to 900 mm, depending on the size and shape of the stones. The stones are typically rough-hewn but are shaped to fit neatly into rows, providing a more uniform appearance compared to uncoursed masonry. 

These stones are sourced from local quarries or natural deposits, such as granite, limestone, and sandstone. The joints between the stones are consistent in thickness, usually around 10mm to 20mm. This masonry style is both strong and aesthetically pleasing, offering a neat, organized appearance while maintaining the natural beauty of stone construction.

Material Estimation:

The quantities of material are the same as of uncoursed rubble masonry.

Cost Analysis:

Using material quantities obtained from the previous step, we will do the cost analysis.   Here the rate considered for materials & labour cost is taken from CPWD DSR 2023. Also, the below table mentions rates of masonry work in substructure as well as superstructure.

For First sort of stone masonry:

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For Second sort of stone masonry:

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General Use:

Coursed rubble masonry is frequently used where moderate strength and durability are needed. It is also popular especially in areas where both strength and aesthetic appearance are important.

Description: Coursed Square Rubble Masonry is a type of stone construction where stones are laid in regular horizontal layers or courses, similar to coursed rubble masonry. However, in this technique, the edges of the stones are made nearly straight, giving them a more uniform and structured appearance, though they are not exactly square. 

The thickness of the joints between the stones is typically 10-15 mm, which is narrower than the joints in coursed rubble masonry, where the thickness generally ranges from 10-20 mm. This results in a slightly more refined finish for coursed square rubble masonry, while still maintaining the natural look of stone construction.

Material Estimation:

The quantities of material are the same, except for stone masonry which is considered without deducting voids occupied for mortar and air, as more dressing of stones is required. So, 

Total volume of stone masonry is 10 m³, and with 25% additional wastage:                            

Total Volume of Rubble Stone (with wastage) =10 m³ × 1.25 = 12.5 m³

Cost Analysis:

Using material quantities obtained from the previous step, we will do the cost analysis.  Here the rate considered for materials & labour cost is taken from CPWD DSR 2023. Since this type of stone masonry is used for aesthetics hence only used in superstructure. So, the below table mentions rates of masonry work above plinth level either in first sort or second sort.

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General Use:

This type of masonry is particularly suitable for both residential and commercial construction that require a combination of strength and aesthetic appeal.

‍Description: Polygonal Rubble Masonry is a type of stone construction where stones are shaped to fit together in a polygonal pattern, meaning the stones have irregular but somewhat angular shapes with multiple sides. These stones are carefully selected and placed in such a way that the joints between them are minimized, providing a strong and stable structure.

The stones used in polygonal rubble masonry are usually large and vary in size, but they are roughly shaped to ensure a good fit, making the construction solid without the need for mortar in some cases, though sometimes mortar is used to fill the gaps.

Material Estimation:

The quantities of material are the same as of uncoursed rubble masonry.

Cost Analysis:

Using material quantities obtained from the previous step, we will do the cost analysis.   Here the rate considered for materials & labour cost is taken from CPWD DSR 2023. Since this type of stone masonry is used for aesthetics hence only used in superstructure. So, the below table mentions rates of masonry work above plinth level either in first sort or second sort.

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General Use:

Polygonal rubble masonry is ideal particularly in areas with abundant stone, where precision and strength are key. Its stability and load distribution make it suitable for constructing piers, bridges, and other load-bearing structures. Additionally, its unique appearance makes it a popular choice for historic buildings and decorative walls.

Description: Dry Rubble Masonry is a type of stone construction where stones are laid without the use of mortar or any binding material. The stones are carefully stacked and arranged, relying on their weight and the interlocking shapes to hold the structure together.

In this type of masonry, the stones are generally larger and thicker at the bottom of the wall, providing a solid and stable foundation. As the wall rises, the stones become thinner towards the top, creating a tapered effect.

The dry stacking of stones allows the wall to "breathe," making it resistant to moisture buildup and helping to manage water flow, which is particularly beneficial for structures in wet or flood-prone areas.

Material Estimation:

Since only stone are laid down without any binding material, So

Total volume of stone masonry is 10 m³, and with 25% additional wastage:                            

Total Volume of Rubble Stone (with wastage) =10 m³ × 1.25 = 12.5 m³

Cost Analysis:

Using material quantities obtained from the previous step, we will do the cost analysis.   Here the rate considered for materials & labour cost is taken from CPWD DSR 2023.

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General Use:

Dry rubble masonry is commonly used for erosion control structures, particularly in areas with stable weather or limited access to mortar. Additionally, dry rubble masonry is suitable for non-load bearing walls or boundary walls, where the structural requirements are less demanding.

Terminologies Used:

Base Rate: 

In construction, the base rate (or base cost) refers to the initial, unadjusted cost of a specific component or resource, such as labor, materials, or equipment, before any additional expenses are factored in. This serves as the foundation for estimating the total costs of a project. The base rate excludes factors like overhead, profit margins, taxes, and other project-specific adjustments, which are added later to determine the final cost. In simple terms, it represents the basic price per unit of resource without any added costs.

First Sort: 

First sort masonry materials are of the highest quality, free from any defects like cracks, chips, or blemishes. These materials are ideal for visible, decorative, or aesthetic applications, often used in the external facades or prominent areas of a building where appearance is essential.

Second Sort: 

Second sort masonry refers to materials that are of slightly lower quality compared to first sort. While still structurally sound and suitable for construction, these materials may show minor imperfections, such as small cracks, discoloration, or surface blemishes. They are generally used in less visible or non-aesthetic areas of a building.

Bond Stones (Through Stones): 

Bond stones, also known as through stones, are essential for ensuring the strength and stability of rubble masonry, particularly in uncoursed rubble masonry. These stones extend across the entire wall from one face to the other, connecting different sections and helping to bind the layers together. The primary purpose of bond stones is to enhance the wall’s ability to bear loads and prevent collapse. According to IS 1597 (Part 1): 2011, bond stones should be substantial in size, typically at least 300mm long with a minimum thickness of 150mm. They should be spaced at regular intervals, usually no more than 1.5 meters apart horizontally along the wall’s length.

Stay tuned for our next blog to explore more about different types of masonry.