Sill blocks are used as windowsills and are designed to seamlessly fit into the building lines. This creates an aesthetically pleasing view of the project and reduces the effort required for contractors and builders to create sills if they do not have access to these blocks. Using sill blocks when building structures with building blocks is highly beneficial as it provides the perfect solution for sills. The dimensions of these blocks are compatible with the building block structure.

Additionally, these blocks are frequently used as a coping for boundary walls. This creates a visually appealing finish to the wall while also preventing rain from penetrating the open block cavities.