The professional term for installing vinyl or wallpaper with an overlap, where each panel extends slightly over the adjacent one, is known as an overlapping seam. This method ensures full coverage, as the panels are deliberately overlapped by a small margin to prevent gaps and create a secure bond. This is the alternative method to applying vinyl with a butted seam. We typically apply a 1″ overlap, but this can be customized to your needs.
Pros:
- Error Margin: Provides a margin for adjustment, making it easier to align panels correctly during installation.
- Full Coverage: Ensures no gaps or missed areas, as the panels slightly overlap.
- Forgiving: More forgiving of minor alignment issues, reducing the risk of visible seams.
Cons:
- Initial Appearance: The overlapping seam may be visible initially before trimming. (It’s more common not to trim and to leave the overlap intact. Resulting in a slightly raised area at the overlap which has two layers of material.)
- Extra Step Required: Requires additional work to slice and remove the top layer for a finished butt seam.
- Potential for Adhesive Build-Up: The overlap can create a slight bulge where the vinyl layers stack, which might be noticeable.
Installation
This approach is particularly effective for large vinyl items and surfaces prone to movement or expansion. The overlap provides a margin of error, making it easier to adjust during installation and reducing the risk of gaps. Even if alignment isn’t perfect, the overlap allows for minor corrections, ensuring a more forgiving installation process, especially for those with less experience.
Trimming (optional) – You can install a large panel item with an overlap, then remove the secondary layer to have a butted seam. This allows you to have the flexibility with installation alignment, but then return it to an edge-to-edge finished product. Once the vinyl is fully installed, the next step is to refine the seam. Using a sharp blade, carefully slice through the center of the overlapping area where the panels meet (careful against certain surfaces that may damage expensive paint). After cutting, remove the top layer of the overlap, which leaves a clean, butted seam. This technique combines the benefits of an overlapping seam during installation with a final, smooth butt joint appearance, providing a seamless and polished finish.
Climate and Surface Reaction
In areas with fluctuating climate conditions, overlapping seams are a reliable choice to counteract the effects of material contraction. As temperature and humidity change, the vinyl or wallpaper might shrink, but the overlap helps maintain coverage and prevents gaps from forming between panels. This technique is especially beneficial in environments with significant seasonal changes, where materials are prone to expanding in heat and contracting in cold.
The type of material and the surface it’s applied to also play crucial roles in how the vinyl or wallpaper behaves. Using overlapping seams with high-quality vinyl, such as cast vinyl or high-performance calendared vinyl, can minimize shrinkage over time. Additionally, the surface’s quality and surface energy influence adhesion and durability, making the overlap method a smart choice for long-lasting installations in challenging conditions.
