Yes, decking boards should have gaps that are ⅛ to ¼ inch wide. These gaps allow for the natural expansion and contraction of the wood. Without the proper spacing between boards, your deck may get damaged. You can get more tips on building a deck in this guide. If you'd like to make sure that your deck will have an adequate gap width, consider hiring a top-rated decking specialist near you. Tap the "Post a task" button to get started on your decking project.