Can you install oriented strand board under siding for extra support?

Oriented strand board, commonly known as OSB, is a type of engineered wood product commonly used in construction. It is made by layering strands of wood together and then compressing and bonding them with adhesive resins and wax. OSB typically comes in 4×8-foot sheets and offers excellent strength and dimensional stability.

Benefits of Using OSB Under Siding:

1. Enhanced Structural Support: One of the primary benefits of installing oriented strand board under siding is the increased structural support it provides. OSB has excellent load-bearing capacity and can help strengthen the overall structure of the building.
2. Moisture Resistance: OSB’s water-resistant characteristics make it an ideal choice for siding installations. It can help protect the underlying structure by acting as a moisture barrier, preventing water damage from rainfall or snow.
3. Cost-Effective Option: Compared to alternatives like plywood or solid wood sheathing, OSB is generally more cost-effective. This makes it a popular choice for builders and homeowners aiming to improve support without breaking the bank.

Installation Process:

Installing OSB under siding requires careful planning and attention to detail. Here are the general steps to follow:

1. Prepare the Surface: Ensure the surface where the OSB will be installed is clean, dry, and free from any debris. Remove any existing siding materials if necessary.
2. Cut the OSB Sheets: Measure the dimensions required and cut the oriented strand board sheets to fit the area. Ensure the sheets are cut accurately to ensure a proper fit and maximum support.
3. Attach the OSB Sheets: Begin by attaching the first sheet of OSB at the bottom of the wall, horizontally. Use exterior-grade nails or screws for fastening, following the manufacturer’s recommendations. Continue attaching the remaining sheets, overlapping them slightly for a stronger bond.
4. Seal the Edges: To prevent potential moisture infiltration, it is recommended to seal the edges of the OSB sheets with an appropriate sealant. This sealing process will further enhance the moisture resistance of the installation.

Considerations and Drawbacks:

While there are several benefits to installing OSB under siding, there are also a few considerations to keep in mind:

1. Local Building Codes: Before proceeding, always check your local building codes and regulations to ensure that adding an additional layer of OSB meets the required structural standards in your area.
2. Weight Considerations: Adding another layer of OSB can significantly increase the weight on the building’s structure. Ensure that the existing structure can bear the additional weight without causing any potential issues.
3. Thermal Performance: OSB alone does not provide significant insulation properties. If insulation is a concern, it is recommended to complement the OSB installation with proper insulation materials to enhance energy efficiency.Adding oriented strand board (OSB) under siding can be a viable option for those seeking extra support in their building’s structure. The use of OSB provides enhanced structural support, moisture resistance, and cost-effectiveness. However, it is essential to consider local building codes, weight considerations, and plan insulation accordingly. Proper installation techniques must be followed to ensure optimal results and long-term durability.