The structural issue of a sagging sofa seat is a common problem resulting from the degradation of its constituent components over time. The appropriate method for remediation depends on the underlying cause, which could be related to cushion compression, spring fatigue, or frame damage.
Based on the provided information, one immediate and non-invasive solution is the use of a heavy-duty cushion support board. This approach involves placing a rigid insert, typically constructed from a material like plywood, directly underneath the sofa cushions. This creates a solid, level base that counteracts the sag by providing firm support and distributing weight more evenly across the seating area. This method is primarily effective for addressing mild to moderate sagging that originates from weakened springs or general wear, offering a simple fix without requiring any disassembly of the furniture.
For a more comprehensive diagnosis, one must also consider the condition of the cushions themselves. Over time, the internal filling, whether foam or fiber, becomes compressed and loses its resilience. In such cases, the remedy involves unzipping the cushion covers and either adding new polyester fiberfill to bolster the existing material or replacing the entire foam core with a new, higher-density block.
If the sagging persists even with firm cushions, the problem likely resides in the sofa's support system. Many sofas utilize a network of zig-zag or sinuous springs. These can stretch, break, or become detached from the frame. Repairing this requires turning the sofa over, removing the bottom dust cover, and inspecting the springs. Corrective actions may include reattaching loose spring clips, replacing broken springs, or adding support twine to link the springs together, which helps to distribute the load more effectively and restore tension. In less common scenarios, the wooden frame itself may be cracked, necessitating structural reinforcement with wood glue and screws.
