Structural Retrofitting for Wood Frame Properties in Southern California: Enhancing Safety and Resilience.
For single, multi-family and commercial property owners with wood frame construction here in California, structural retrofitting is essential for enhancing safety and resilience.
Understanding Structural Retrofitting
Structural retrofitting involves upgrading a building’s structural system to withstand seismic forces more effectively. Older wood frame structures may not meet current building codes, making retrofitting crucial to reduce the risk of damage during an earthquake. Investing in retrofitting enhances safety and preserves property value like here for example, at a recent project we here at Costo Construction managed recently while restoring this commercial building.
Key Retrofitting Techniques
1. Brace and Bolt
The Brace and Bolt method uses bracing to enhance the lateral stability of wood frame construction, including single family homes built with cripple walls at their bases. A few manufacturers, including Simpson Strong-Tie, offer a wide range of products specifically designed for this purpose.
How It Works:
- Bracing Installation: As examples, Simpson Strong-Tie® LTP4 or LTP5 tension ties secure framing members and braces and Universal Retrofit Foundation Plates (URFP) provide secure connections between recessed sole plates and foundation walls ensuring that forces are effectively transferred throughout the structure. Bracing will generally also include plywood added to the interior or exterior of wall framing, wood blocking and hold down hardware is added between studs and connected to foundation walls.
- Bolting to Foundation: The use of Simpson Strong-Tie® ABU anchor bolts, which come in various sizes, allows for robust anchoring of the wood frame to the foundation. These bolts are designed to handle significant shear and tension forces, reducing the risk of sliding during seismic events.
- Foundation Upgrades: Simpson Strong-Tie® hold-downs like the HDU or H1 series connect the shear walls to the foundation, ensuring that the soft story construction stands its best chance to withstand seismic forces without collapsing.
Benefits of Brace and Bolt:
- Increased lateral stability
- Reduced risk of structural failure
- Enhanced overall safety for occupants
2. Soft Story Improvements
Soft stories, typically characterized by large openings for garages or storefronts, or under building carports, can pose serious risks during an earthquake. There are a variety of products and solutions that can help reinforce these vulnerable areas effectively.
How It Works:
- Reinforcement of Soft Stories: Simpson Strong-Tie® shear wall solutions, such as the Shear Wall Kit, or Moment Frames provide pre-engineered components that can be installed to enhance the rigidity of soft story areas. These kits include shear wall panels and connectors specifically designed for seismic applications.
Benefits of Soft Story Improvements:
- Enhanced safety and structural integrity
- Protection against potential collapse
- Increased property value and marketability
The Importance of Professional Assessments
Structural retrofitting is complex and requires expertise. Having your property assessed by a qualified structural engineer and a qualified contractor is crucial for several reasons:
Comprehensive Evaluation
A structural engineer will conduct a thorough inspection of your property, identifying vulnerabilities and assessing the existing structural systems. This evaluation is vital for developing a customized retrofitting plan that meets your property’s specific needs. Further evaluations and testing may need to be done by Geo-Technical Engineers to provide information and prescribe calculations and designs for Structural Engineers to include in their own design work.
Tailored Solutions
Based on the assessment, a structural engineer can recommend the most effective retrofitting techniques, including the appropriate Simpson Strong-Tie or other products for Brace and Bolt or Soft Story improvements. This tailored approach ensures your property is fortified effectively.
Peace of Mind
Investing in structural retrofitting not only enhances your property safety but also provides peace of mind. Knowing that your property is better equipped to withstand seismic activity allows owners and tenants to live and work confidently in a seismically active region.
Long-Term Savings
While the initial cost of retrofitting may seem significant, it is a proactive measure that can save owners from costly repairs after an earthquake. Furthermore, properties that are retrofitted often see an increase in property value, making it a wise investment.
Where we fit in:
Costo Construction Corp. is listed with the California Residential Earthquake Mitigation Program. The program administers grants to select property owners through the California Earthquake Authority and FEMA.
Beyond this, we have decades of experience performing and managing structural upgrades whether it be structural shoring & framing, helical screw pile installations, structural concrete underpinning, grade beams, and other foundation work. This work generally involves geo-technical and hydro-technical engineering as well and we have experience with soil testing including drill rig coring, concrete scanning, ground penetrating radar, geo-locating, stormwater management systems, oil tank removal and remediation and condition reports etc.
If you are concerned about the condition of your property and would like to discuss the solutions, feel free to reach out to us to learn more. Rebuilding buildings involves building the correct teams. We collaborate with architects and engineers and a whole host of specialized skilled and properly equipped trades and manufacturers to solve seismic issues. We also develop full scopes of work, budgets and schedules and we also can acquire the required building permit from the local authority.
