Step 4 · Insert and Secure Shims

Carefully tap the glued shims into the identified gaps using a hammer. The goal is to create a snug fit that eliminates any looseness. Once the shims are in place and the movement is reduced or eliminated, you can add glue blocks. Cut small triangular blocks of wood and glue them in the corners where the tread meets the riser and stringer, providing extra support and further preventing movement. You can also drive short screws through the stringer into the tread or riser if needed, but be careful not to split the wood or penetrate through the visible side of the tread.

Tools and Materials