Backsplashes protect the back wall behind a counter from splashing and spilled liquids, splattering grease and other messes. The backsplash material is much simpler to clean than a painted wall. Backsplashes can range in height from a few inches sticking over the counter to a full wall’s worth running up to the cabinets above the counter. The type of backsplash usually depends on its purpose, and butcher-block counters tend to have the shorter backsplashes like those seen with tile counters.
For countertops by a wall, install a matching wood backsplash. These are just solid planks of wood that may have a sanded edge for decoration. Butcher-block manufacturers usually sell coordinating parts, but for old, repurposed countertops that don’t have available options, look for a similar color and grain to best match what you have. After installing the countertop, attach the backsplash to the wall and have it sit on top of the countertop. The Wood Welded website advises that the backsplash should not sit between the edge of the countertop and the wall. Spread glue on the wood and press the backsplash in, cleaning away any extra glue that you can see poking over the top. When that has dried, caulk the edges of the backsplash at the countertop and wall.
Butcher-block counters that are on separate islands can have a similar type of backsplash held on with nails and glue. The backsplash can be on just one side or on two or three. In the book "Black and Decker Easy Wood Furniture Projects: 32 Step-by-Step Projects for the Home," authors advise fitting the backsplash on top of the block at the edge and drilling pilot holes up through the bottom of the block into the backsplash. After applying glue to the bottom of the backsplash, secure it to the block by drilling screws in using the pilot holes as guides.
An additional factor to consider is if the island has a built-in cooktop. Splatters from cooking can travel far, and a counter-edge backsplash may be too far away and too short to prevent much of the mess. In these cases, a three-sided splatter guard might be a more suitable backsplash. These are temporary guards that you stand up around the back and sides of the cooktop; they don’t anchor permanently into the butcher-block. Reusable ones made of metal are available online, or you can buy foil guards at Asian groceries and online. The foil guards bend easily so be careful not to knock them around if you want one to last a long time.