Post-Tensioning: Change-In-Use of Existing Buildings

When a commercial building gets old or is used for a different purpose than its original design, renovations may be required. These renovations may also require code changes for the building. To do this, engineers have to apply for change-of-use or change-in-use permits. 

By way of example, let’s imagine that you own an apartment building that was built without an elevator. Adding an elevator means following new construction codes that were not previously required. While adding an elevator seems like an easy change, it impacts much more than just the convenience of residents. The addition of an elevator impacts load bearing capacities and structural integrity. This is why it is key to properly analyze the concrete and install post-tensioned and pre-cast concrete parts. 

Read on to learn more about how post-tensioning systems are vital for many scenarios for change-in-use construction of existing buildings.

Change-In-Use of Building Considerations

Change-in-use of an existing building is enormously important because of the structural changes that occur when you begin to remove walls and add systems. There are many aspects of a building that engineers have to keep in mind when completing these projects. Here are a few:

• Ductwork and airflow
• Load bearing walls
• Water and sewage systems
• Electrical systems
• Handicap accessibility
• Fire codes and building codes

These are very basic and broad aspects that engineers consider when completing change-in-use projects. Many times, before this type of construction or remodeling even begins, concrete scanning and coring must be conducted.

Concrete Scanning and Coring

When remodeling buildings with concrete elements, it is crucial to understand the systems contained within the concrete. For example, wiring, water pipes and tendons may be located within certain sections of the concrete. Engineers use concrete scanning technologies for precise locating and marking of these internal systems. 

Coring is another important part of preparing for change-of-use remodeling. Concrete coring is the process of removing a small, cylindrical section of concrete to test for structural integrity. It is used for concrete repairs and replacements as well as remodeling.

Scanning and coring are excellent ways to find out more about the sections of concrete that may need to be changed or removed. 

Post-Tensioning for Change-In-Use

Post-tensioning is often used in change-in-use applications for a few different reasons. The first, and most important, is that post-tensioned systems come in precast concrete. The use of precast concrete makes it possible for construction to continue at a faster pace. It also saves money in labor and materials. 

The second benefit of using post-tensioning for change-of-use remodeling is that it has the ability to increase the structural integrity of a building. Need to add a stairwell? Want to install an elevator? These are both examples of remodeling projects that would require the use of post-tensioning. 

Here are more benefits of using post-tensioning systems in change-of-use projects:

• Resistant to corrosion
• Easily repairable with epoxy injections and coatings
• Less expensive than form-in-place concrete
• Easy to adapt to a variety of applications

There are a few ways in which post-tensioning is used in change-in-use. Here are two of the most common applications:

Post-Tensioned Girder

Often, support beams are needed for major change-in-use renovations in commercial buildings. These support beams are called girders. They are designed in a variety of shapes and sizes. One of the most common ways that they are designed is with the addition of steel tendons through post-tensioning. These tendons allow for better customization of the dispersal of weight as well as provide a high quality, long-term solution. 

External Post-Tensioning

This technique is often used in concrete restoration for new features such as openings, loading conditions and elevators. External post-tensioning works by placing the tendons on the outside of the concrete. Using anchorages, saddles and deviators, the tendons are able to transfer their force into the concrete. This provides excellent structural support without the need for demolition. Here are some of the advantages to using external post-tensioning:

• More economical than demolishing and re-installing new concrete slabs
• Easy to maintain and monitor
• Simple construction and tendon layout
• Used in a wide range of applications

Overall, external post-tensioning is a great way to achieve the structural support necessary to meet code requirements without breaking the bank. 

Post-Tensioning Services for Change-In-Use

Looking for a post-tensioning service for change-of-use remodeling? Consider Tendon Systems. Based in Georgia, but with ongoing projects all across the United States, our team of engineers is ready to help you with your change-in-use project.

From high tech scanning and coring to post-tensioned, precast concrete, we have got your back. Don’t let code changes discourage you from accomplishing the renovations you want. 

If you aren’t sure how to approach your project or you need one of our many services, give us a call at (678) 835-1100 or visit our website: https://www.tendonllc.com/post-tensioning-systems.