High-Density Fiberboard (HDF) is an engineered wood product that's similar to Medium Density Fiberboard (MDF), but is denser and much harder. It is made by breaking down hardwood or softwood residuals into wood fibers, often in a defibrator, combining it with wax and a resin binder, and forming panels by applying high temperature and pressure.
Characteristics of HDF:
- Density: As the name suggests, HDF has a high density, typically 800 kg/m³ or more, which is achieved by the addition of more wood fibers per unit volume during manufacturing.
- Strength and Durability: Its high density gives it strength and makes it more durable than its MDF counterpart. It provides a better holding strength for screws and fasteners and is less likely to sag than other composites.
- Surface Smoothness: HDF has a smooth surface that is excellent for painting and applying veneers or laminates. This makes it a popular choice for furniture, cabinetry, and flooring underlayments.
- Moisture Resistance: Despite being denser, HDF is not inherently resistant to moisture. However, moisture-resistant and waterproof HDF variants are available for uses where exposure to water is a concern.
- Machinability: HDF can be easily cut, drilled, and machined without splintering, although its hard nature can result in quicker wear on cutting tools.
- Environmental Impact: Because HDF is manufactured from wood fibers, it consists of either post-industrial recycled materials or forest thinning, considered environmentally friendlier than solid wood extraction. However, the resins used can sometimes contain formaldehyde or other VOCs (Volatile Organic Compounds), raising environmental and health concerns.
