About Exterior Wood Stain Our exterior wood stain has been developed for staining all types of wood used outdoors. It is based on the same technology as our regular Wood Stain, but is made a little thicker to suit exterior wood. This means it can also be used on interior wood too (if you prefer one of our exterior wood stain colours). It is a great garden furniture wood stain, and can also be used to stain windows, doors, cladding and all other items of exterior wood. After using the Exterior Wood Stain, we recommend treating the wood with Teak Oil. This will help protect the wood and keep it looking newer for longer.