Shims are ideal for minor rocking caused by uneven flooring or a slight gap at the base. If the wobbling is significant, accompanied by leaks, or if the toilet moves freely from the floor, you might have loose flange bolts, a damaged wax ring, or a compromised subfloor, which requires more extensive repair than just shims.

Yes, securing a wobbly toilet with shims is a beginner-friendly DIY task. Most of the time is spent diagnosing, inserting shims, and applying caulk. With the recommended tools and materials, a novice can typically complete it within the estimated 2 hours, assuming no unexpected issues like a broken flange.

While the listed tools like a utility knife and adjustable wrench are highly recommended for efficiency and safety, some generic equivalents can work. For example, a basic screwdriver set can replace the specialized flathead, and any sharp utility knife will trim shims. However, a good caulk gun is essential for a clean, professional finish.

A common mistake is overtightening closet bolts, which can crack the toilet base. Another is not checking all sides for gaps, leading to uneven shimming. Prevent this by gently hand-tightening bolts first, then incrementally shimming around the entire base until the toilet is stable, ensuring even contact.