Fire door materials composition can vary, but the most common types are:
Typically, solid timber sections are laid out to make a four-sided frame. The inner part is then filled by a core and both sides are bonded with plywood, chipboard or MDF. This design offers a lighter door with the strength, stability and screw retention of a solid, more expensive timber door. Stile and rail doors offer the same benefit as solid timber doors, but they are more cost-effective. PAL Doorsets use traditional stile and rail construction method and the core of every VLine doorset is 100% recycled, lightweight and stable. MDF or HDF encasing creates a solid and durable subsurface, ready for final finishing with foil, veneer, 3D skin or laminate.
Produced from solid, jointed timber blanks. Often finished with either plywood, MDF or chipboard subfaces. These are used for external (ply faced) or internal applications where a much more robust construction is called for, such as hospital corridors, schools or seclusion rooms. These blanks are edged (lipped, 6-20mm) in timber and finished in either paint, veneer or laminate. Due to the volume of timber and the specialised nature required to make these blanks, the cost of the overall doorset can be high.
Produced from non-timber-based fire door materials, such as diatomaceous earth. Often this type of build resembles that of the stile and rail construction. Primarily, these highly specialized doors are found where very high fire ratings are required (FD90 and above, used in carparks, airports, hospitals etc.).
This type of door is more commonly used on external applications and traditionally had a PU foam core. Recent testing by the Ministry of Housing, Communities & Local Government highlighted that fire doors with PU foam core often fail the fire testing and emit very high levels of toxic smoke in a fire. As a result, core materials are now mostly solid timber with a GRP or PVC skin applied over the top. If used internally, GRP or PVC skins could cause toxic smoke that are dangerous in a closed environment. These doors are less environmentally friendly as they often disposed of as general waste to landfill (skins are not recyclable / breaking the door down to elements can be costly).
These blanks are produced from solid particleboard. The finish can be either paper, paint, veneer or laminate. Chipboard doors are very inexpensive to make; but often sold at a similar price as other fire doors, despite the potential differences in appearance, durability and longevity. Common issues can be telegraphing (thin edge detail shines through the face finish), chipping of finishes and poor screw retention.