When we think about sustainable construction, energy efficiency and environmentally friendly building materials often come to mind. But seismic retrofitting and sustainability are also connected through an important consideration: preserving and improving the buildings we already have.
For commercial and industrial property owners, sustainability can also involve making thoughtful decisions about existing structures. When an older building has seismic vulnerabilities, strengthening it rather than replacing it may offer environmental advantages.
However, the best approach depends on the building’s condition, intended use, and required improvements.
The Environmental Value of Existing Buildings
Constructing a building requires substantial amounts of concrete, steel, masonry, and other materials. Manufacturing, transporting, and installing these materials generate greenhouse gas emissions, contributing to what’s known as embodied carbon.
Unlike operational carbon, which comes from energy used to heat, cool, and operate a building, embodied carbon reflects emissions associated with building materials and construction processes throughout their life cycle.
When an existing building is demolished and replaced, new construction adds embodied carbon. Retaining usable structural components can help avoid some of those emissions.
THE VALUE OF BUILDING REUSE
When evaluating a building’s environmental impact, consider not only the materials needed for improvements but also the resources required to demolish and replace the existing structure.
This is one reason building reuse has become an important consideration in sustainable construction. However, the environmental benefits depend on how much of the existing structure can be retained and what improvements are needed.
What Can Seismic Retrofitting Preserve?
Seismic retrofitting strengthens existing buildings by addressing structural vulnerabilities identified through engineering evaluations. Rather than replacing an entire structure, the work typically involves adding or modifying specific structural components.
For example, an older concrete tilt-up building may need improved wall-to-roof connections and continuity ties to address seismic deficiencies. An older reinforced concrete building may require similar improvements, along with new shear walls, strengthened columns, or foundation improvements.
These modifications can improve seismic performance while allowing much of the original building to remain intact.
This approach can be particularly valuable for commercial and industrial properties that still meet their owners’ operational needs but were built before modern seismic design requirements.
Historic buildings present another consideration. Beyond their physical materials, these structures may have architectural or cultural significance worth preserving. As discussed in our article on historic buildings and earthquake risk, seismic improvements must often balance structural requirements with preserving historically significant features.
Of course, not every building is a suitable candidate for retrofitting. Some structures may require extensive improvements that affect the feasibility or environmental advantages of preservation.
RETROFIT OR REBUILD?
The most sustainable choice isn’t always the one involving the least construction. Building condition, required improvements, future use, and long-term performance all influence the decision.
Retrofitting vs. Rebuilding: What Should Property Owners Consider?
When an older building requires substantial structural improvements, property owners may need to evaluate whether retrofitting or rebuilding makes more sense.
Seismic retrofitting can often be completed more quickly than demolishing and constructing a new building, potentially reducing downtime and business disruption. Retrofitting may also offer tax advantages, depending on the nature of the improvements and applicable tax regulations.
Although retaining existing materials can offer environmental advantages, seismic retrofitting also requires steel, concrete, equipment, transportation, and other construction resources. The extent of those requirements matters when comparing the two approaches.
Several factors can help guide the decision.
1. Existing Structural Condition
A building with a generally sound structural system may be a stronger candidate for retrofitting than one with widespread deterioration or significant structural deficiencies.
A qualified structural engineer can evaluate existing conditions, identify vulnerabilities, and determine what improvements would be necessary.
2. Scope of Required Improvements
Some retrofits involve relatively targeted structural modifications, while others require extensive work throughout the building.
For example, strengthening wall-to-roof connections in a tilt-up building presents a different construction scope than adding new structural walls and foundations to a multistory concrete structure.
Understanding the anticipated scope helps owners evaluate material requirements, construction costs, and potential environmental impacts.
3. Future Building Use
A building’s ability to meet current and future operational needs is another important consideration.
Changes in occupancy, equipment, loading requirements, or building configuration may affect whether rehabilitation is practical.
For occupied commercial and industrial properties, the construction process itself also matters. Depending on the scope, seismic retrofitting may allow portions of a building to remain operational during construction.
At Saunders Seismic, minimizing disruption to tenants and business operations is central to how we plan and execute projects.
4. Long-Term Building Performance
Environmental considerations extend beyond initial construction.
Energy efficiency, maintenance requirements, anticipated service life, and future renovation needs all influence a building’s overall environmental footprint.
A life-cycle assessment can help compare the environmental impacts of different rehabilitation and replacement scenarios, rather than evaluating construction materials alone.
Ultimately, neither retrofitting nor rebuilding is automatically the more sustainable choice. The appropriate solution depends on the specific building and the owner’s long-term objectives.
Strengthening Existing Buildings for the Future
Saunders Seismic has specialized in commercial and industrial seismic retrofitting for more than forty years.
Our clients often say, “I didn’t know it could be so easy!” Our experienced in-house crews work with owners, engineers, and project teams to implement practical structural solutions, often while buildings remain occupied and operational.
Whether you’ve received a seismic retrofit notice, are working with a structural engineer, or are simply exploring options for an older building, we’re happy to discuss your situation.
Contact Saunders Seismic to discuss your building’s needs and explore next steps.
