Wooden doors come in three types: solid wood, solid core and hollow core. As you would expect, solid wood doors are made from thick slabs of wood. They are strong, secure and are good insulators. They are also rather costly which makes them a natural choice for external doors. Solid core doors have a thin veneer of high-quality natural wood fixed over a core of engineered wood, such as HDF. Hollow core doors, contrary to their name, do not have an empty void at their centre. Instead they have a thick solid frame, and a core made of plastic or cardboard. This core is usually constructed in a hexagonal ‘honeycomb’ pattern; one of the strongest structures found in nature. This makes the doors more solid, robust, and soundproof. Hollow core doors are lightweight, easy to fit and inexpensive, which makes them a popular choice for internal doors. They are also very versatile. This honeycomb core can be contained within a variety of veneers that can be matched to any decor. They can even be made to resemble far more expensive solid wood doors.