Understanding the Term “Knocked Out” in Construction: A Comprehensive Guide

In the world of construction, terminology can sometimes be specific to the industry, and understanding these terms is crucial for clear communication and proper execution of tasks. One such term frequently used is “knocked out”. While it may sound like something that happens in a boxing ring, in construction, it refers to a particular process that has significant implications for the structural integrity, utility systems, and overall design of a building. In this article, we will dive deep into the meaning, applications, and importance of being “knocked out” in construction projects.

What Does “Knocked Out” Mean in Construction?

The term “knocked out” in construction refers to the intentional creation of an opening or void in a material or structure, typically within concrete, masonry, or metal components. These openings are pre-designed, either as spaces for future installations or as part of the building’s design. For example, contractors often create a knocked-out section in a wall, floor, or ceiling to later install pipes, electrical conduits, or ducts. This process is critical for ensuring that the infrastructure meets the functional and safety requirements of the building.

Applications of Knocked-Out Sections in Construction

The use of knocked-out sections is widespread across various types of construction projects. Here’s how they are commonly applied:

1. Pre-Planning for MEP (Mechanical, Electrical, and Plumbing) Systems

One of the most common uses of a knocked-out section is in the installation of MEP systems. This includes ductwork, pipes, and wires that are essential for the building’s functionality. During the construction of floors and walls, knocked-out openings are pre-installed at strategic locations, allowing easy access for these systems.

For example:

• Piping: A knocked-out opening in a concrete slab allows space for piping to be laid out later during the plumbing stage.
• Electrical Conduits: Electrical contractors use knocked-out sections to route wiring through walls or ceilings.
• HVAC Systems: Knocked-out sections in the wall or ceiling are typically used to route air ducts for heating, ventilation, and air conditioning systems.

2. Structural Adjustments and Load Distribution

In some instances, knocked-out sections are necessary for making structural adjustments. For example, a knocked-out section in a reinforced concrete wall could be used to create an opening for a door or a window without compromising the load-bearing integrity of the structure. In these cases, engineers must ensure that the knockout sections are properly reinforced to maintain the building’s strength.

3. Aesthetic and Design Considerations

Knocked-out sections can also be used to create intentional spaces in the design of a building. For example, architectural features like arched windows or decorative cutouts may be created through knocked-out openings. These aesthetic choices can enhance the visual appeal of both the interior and exterior spaces, contributing to the building’s overall design.

Types of Knocked-Out Sections in Construction

The term knocked-out applies to various types of openings created in different materials. Here’s an overview of the most common types:

1. Knocked-Out in Concrete

In concrete construction, knocked-out sections are often used to create access points for utility lines, electrical conduits, and pipes. These openings are formed when the concrete is poured, typically using a removable form or a temporary insert during the curing process. Knocked-out concrete is then removed to create the space needed for the installation of MEP systems.

Key considerations include:

• Ensuring the knockout is done at the right stage of the pour to avoid compromising the concrete structure.
• Reinforcement of the surrounding area to maintain the integrity of the slab or wall once the knockout is created.

2. Knocked-Out in Steel and Metal Structures

In steel construction, a knocked-out section might refer to a pre-punched hole in a steel beam or column, created for routing cables, pipes, or air ducts. These holes are often part of the original design and allow for a streamlined installation process, ensuring the utility systems can be placed without additional drilling or modification later.

3. Knocked-Out in Masonry

In masonry construction, knocked-out sections are created in brick or stone walls to allow for the passage of pipes, ducts, or cables. This is often done by removing specific bricks or stones during construction. In some cases, a mortar joint is left intact, which can be easily removed later to create the necessary void.

4. Knocked-Out in Drywall

For drywall applications, knocked-out sections are typically used to create openings for light switches, outlets, and ventilation systems. These openings are generally made during the drywall installation process and are often used to prepare the wall for later finishing and fitting.

Why are Knocked-Out Sections Important in Construction?

Knocked-out sections are not only essential for the installation of utilities but also for ensuring construction efficiency. These pre-designed openings allow the construction process to run smoothly without the need for retrofitting or additional modifications once the walls or floors are in place. By planning these openings early on, contractors can save time, reduce the need for complex work, and avoid unnecessary delays.

Additionally, the presence of knocked-out sections allows for greater flexibility. If a future need arises for additional utilities or systems, a knockout can be created and customized to suit those requirements. This can be particularly helpful in commercial or industrial projects, where changes in use or tenant needs are common.

Considerations for Creating Knocked-Out Sections

While knocked-out sections are beneficial in many aspects, creating them must be done with care. Here are some essential considerations:

• Location: Knocked-out sections should be placed strategically, avoiding critical load-bearing areas of the structure. Improper placement can compromise the structural integrity of the building.
• Size: The size of the knocked-out section should align with the planned utilities and ensure there is enough space for installation and future maintenance.
• Reinforcement: After a knockout is made, additional reinforcement may be necessary to maintain the strength and stability of the surrounding materials. This is particularly crucial for concrete and masonry structures.
• Sealing: Once utilities are installed through knocked-out sections, it’s important to properly seal the openings to prevent air leaks, water infiltration, or pest intrusion.

Conclusion

The term “knocked out” in construction refers to the intentional creation of an opening or void in a structure, typically for the installation of utilities or for design purposes. These openings, whether in concrete, steel, masonry, or drywall, play an essential role in ensuring that buildings meet both functional and aesthetic needs. By planning these openings early in the construction process, builders can improve efficiency, cost-effectiveness, and flexibility in adapting to future changes.

Understanding how and why knocked-out sections are used is crucial for both contractors and property owners. This knowledge ensures that construction projects run smoothly, with minimal delays or complications arising from utility installations or structural changes.

For more information on construction terminology and techniques, check out this article: Define Knocked Out in Construction.