Yes, wainscoting can be installed on uneven walls, but it requires additional preparation. Using shims behind the panels is a common technique to level the surface and ensure alignment. Filling gaps with caulk or wood filler can also help create a smooth, seamless look. If the walls are significantly uneven, hiring a Toronto trim carpentry contractor is highly recommended. Professionals have the tools and expertise to address irregularities, ensuring a flawless installation.