Shoring in Construction : Types & uses

Shoring is a vital process in construction that involves creating temporary structures to support an unstable building or structure. This method is essential for ensuring safety and stability during various construction activities, such as repairs, demolitions, and modifications. Shoring supports walls laterally and prevents potential collapses or further damage. you may also consider to Underpinning as People often get confused between these two. In this blog we will discuss about shoring in detail.

What is Shoring?

Shoring is a technique where temporary supports are built to stabilize and support structures, preventing collapses during repairs or alterations. It ensures safety and structural integrity.

There are three main types of shoring used in construction: raking shoring, flying shoring, and dead shoring. Each type serves specific purposes and is chosen based on the requirements of the construction project.

1. Raking Shoring

Raking shoring is a common method that uses inclined members, known as rakers, to provide lateral support to walls. This type of shoring consists of several components, including rakers, wall plates, needles, cleats, bracing, and sole plates. The rakers are inclined members that are positioned to support the wall at an angle, typically between 45 and 75 degrees. Here are some key considerations for using raking shores:

– Inclination: Rakers should ideally be inclined at a 45-degree angle to the ground. However, the angle can vary between 45 and 75 degrees based on the specific requirements.
– Rider Rakers: For tall buildings, the length of the rakers can be reduced by introducing rider rakers, which provide additional support.
– Bracing: Rakers should be properly braced at intervals to ensure stability.
– Anticipated Thrust: The size of the rakers should be determined based on the anticipated thrust from the wall.
– Meeting Point: The centerline of a raker and the wall should meet at the floor level.
– Spacing: Shoring may be spaced at intervals of 3 to 4.5 meters to cover a longer length of the wall.
– Sole Plate: The sole plate should be properly embedded into the ground at an inclination and be of the appropriate section and size.
– Avoid Wedges: Wedges should not be used on sole plates, as they may give way under vibrations that are likely to occur.

Raking shoring can be particularly effective for buildings that are showing signs of lateral stress or instability. Proper installation and maintenance are crucial to ensure the safety and effectiveness of the shoring.

2. Flying Shoring

Flying shoring provides temporary support to the party walls of two buildings when the intermediate building is to be demolished and rebuilt. This method involves various arrangements where the shores do not reach the ground. Flying shoring consists of wall plates, needles, cleats, horizontal struts (commonly known as horizontal shores), and inclined struts arranged in different forms based on the situation. Here’s how flying shores work:

– Wall Plates: Wall plates are placed against the wall and secured to it.
– Horizontal Strut: A horizontal strut is placed between the wall plates and is supported by a system of needles and cleats.
– Inclined Struts: The inclined struts are supported by the needle at their top and by straining pieces (or straining sills) at their feet. The straining piece is spiked to the horizontal shore and has the same width as the strut.
– Trussed Framework: When the distance between the walls is considerable, a trussed framework of members is necessary to perform the function of flying shore safely.

Flying shoring is essential for projects where ground access is limited or not feasible. It allows for structural support without interfering with ground-level activities, making it an efficient solution for many urban construction sites.

3. Dead Shoring

Dead shoring is used to provide vertical support to walls, roofs, and floors when the lower part of a wall is removed to create an opening or to rebuild a defective load-bearing wall. Dead shoring involves an arrangement of beams and posts that support the weight of the structure above and transfer it to a firm foundation below. The process of dead shoring includes the following steps:

– Cutting Holes: Holes are cut in the wall at a height that allows sufficient space for the insertion of a beam or girder that will be permanently placed to carry the weight of the structure above.
– Needles: Beams called needles are placed in the holes and are supported by vertical props called dead shores at their ends on either side of the wall. Needles can be made of timber or steel and must be of sufficient section to carry the load above.
– Working Space: The dead shores stand away from the wall on either side to allow for working space when the needle and the props are in position.
– Securing Props: The props are tightened using folding wedges provided at their bases, while the junction between the prop and the needle is secured with the help of dogs.
– Relieving Load: Before starting the dismantling work, all doors, windows, or other openings are well strutted to relieve the wall of the load of floors and the roof above.

Dead shoring is particularly useful when significant structural changes are required, such as adding new openings or replacing sections of a load-bearing wall. It ensures that the building remains stable throughout the construction process.

4.Trench Shoring

• Used in deep excavation work to prevent soil collapse.
• Includes timber, steel plates, or hydraulic trench boxes to support trench walls.
• Essential for pipeline installation, foundation work, and sewer construction.

5. Sheet Piling

• Used for large-scale excavation and water retention projects.
• Involves driving steel, timber, or concrete sheets into the ground to create a strong barrier.
• Common in harbour construction, riverbank protection, and basement work.

Uses of Shoring in Construction

Shoring is a versatile construction technique used to provide temporary support and ensure the stability of structures during various stages of building, repair, and modification. Here are some key uses of shoring:

1. Supporting Unstable Structures

• Bulging or Leaning Walls: When walls exhibit signs of bulging or leaning, shoring provides the necessary lateral support to prevent further movement and potential collapse.
• Cracked Walls: Walls that have cracked due to uneven foundation settlement can be temporarily supported with shoring until permanent repairs are made.

2. During Excavation

• Trench Shoring: Shoring is essential for stabilizing the sides of trenches during excavation to prevent cave-ins and ensure the safety of workers.
• Basement Construction: When constructing basements, shoring supports the surrounding soil and existing structures to prevent collapses during the excavation process.

3. Renovation and Repair

• Creating Openings: Shoring is used to support walls, floors, and roofs when creating new openings or enlarging existing ones, such as doors and windows.
• Foundation Repair: In underpinning projects, shoring provides temporary support to the structure while the foundation is being repaired or strengthened.

4. Demolition

• Partial Demolition: During the partial demolition of buildings, shoring supports the remaining structure to prevent it from collapsing.
• Adjacent Buildings: Shoring is used to support adjacent buildings when one building in a row is demolished to prevent the shared walls from collapsing.

5. Construction of Multi-Story Buildings

• Supporting Upper Floors: When lower floors are being constructed or modified, shoring supports the upper floors to maintain the building’s stability.
• Temporary Support During Construction: Shoring provides temporary support to structural elements until the permanent supports (such as beams and columns) are installed and secured.

6. Emergency Situations

• Disaster Response: In the aftermath of earthquakes, landslides, or other natural disasters, shoring is used to stabilize damaged buildings and prevent further collapse, allowing rescue operations to proceed safely.
• Fire-Damaged Structures: Buildings damaged by fire may require shoring to support weakened structures and ensure safety during inspections and repairs.

7. Infrastructure Projects

• Bridge Construction: Shoring is used to support bridge decks and other components during construction or repair.
• Tunnel Construction: In tunnel construction, shoring stabilizes the tunnel walls and ceiling to prevent collapses.

Advantages of Shoring in Construction

Shoring plays an important role in construction projects by offering multiple benefits:

1. Prevents Structural Collapse – Provides essential support for excavation and old buildings.
2. Ensures Worker Safety – Protects labourers working in deep trenches or unstable areas.
3. Maintains Stability – Helps retain the strength of nearby structures.
4. Facilitates Deep Excavation – Allows safe digging for basements, tunnels, and foundations.
5. Reduces Risks & Accidents – Prevents soil collapse and structural damage.
6. Improves Construction Speed – Enables workers to complete excavation safely and efficiently.
7. Supports Heavy Loads – Helps stabilise buildings during modifications.
8. Useful in Urban Construction – Ideal for supporting structures in densely populated areas.

Disadvantages of Shoring in Construction

While shoring has many advantages, it also comes with some challenges:

1. High Cost – Materials and installation can be expensive.
2. Time-Consuming – Requires proper planning and execution.
3. Material Selection Issues – Choosing the right type (wood, steel, or concrete) depends on soil and structure conditions.
4. Regular Maintenance Needed – Temporary structures must be checked frequently.
5. Environmental Impact – Some shoring methods may disturb surrounding areas.
6. Labour Intensive – Skilled workers are required for proper installation.

Applications of Shoring 

Shoring is widely used across various construction projects including:

• Metro rail projects – Used in deep excavations for underground metro stations.
• Highway and bridge construction – Supports soil during excavation near roads.
• Old building restoration – Prevents wall collapse during repair work.
• Real estate projects – Essential for basement and multi-storey construction.
• Waterfront construction – Used in ports and riverbank protection.

IS Codes for Shoring in Construction

In India, shoring design and installation follow guidelines set by the Bureau of Indian Standards (BIS) and other authorities. Some relevant IS codes include:

• IS 3764:1992 – Safety code for excavation work.
• IS 1904:1986 – Design guidelines for foundations and soil protection.
• IS 1080:1985 – Code for shoring and timbering in excavation.
• IS 456:2000 – Code for reinforced concrete design (used in sheet piling).

Following these standards ensures safety, durability, and efficiency in construction projects.

Important Considerations for Shoring

– Material Selection: The choice of materials for shoring (timber, steel, etc.) should be based on the load requirements and the duration of the support needed.
– Inspection and Maintenance: Regular inspection and maintenance of shoring structures are crucial to ensure their integrity and effectiveness. Any signs of wear, damage, or displacement should be addressed immediately.
– Safety Protocols: Proper safety protocols, including the use of personal protective equipment (PPE) and adherence to construction safety standards, are essential to protect workers involved in shoring operations.
– Environmental Factors: Consideration of environmental factors such as weather, soil conditions, and surrounding structures is important when planning and executing shoring activities. Adverse conditions can affect the stability and effectiveness of shoring.
– Professional Expertise: Employing experienced engineers and construction professionals is critical for the design and implementation of shoring systems. Their expertise ensures that the shoring is adequate and effective for the specific project requirements.

Conclusion🎯

In conclusion, shoring is a critical technique in construction that ensures the safety and stability of structures undergoing repairs, demolitions, or modifications. By understanding and implementing the appropriate type of shoring—whether raking, flying, or dead shoring—construction professionals can effectively manage the risks associated with unstable structures and maintain a safe working environment. Proper planning, material selection, and adherence to safety protocols are essential for the successful execution of shoring in construction projects.