With its attractive easy-to-clean surface, and its resistance to abrasion, scuffing and impact, Formica® decorative laminate provides an excellent durable and maintenance-free cladding material for doors in both industrial and institutional installations. This is especially relevant to hospitals and laboratories which require an easily cleaned, hygienic surface.
Laminate Grade
Although doors are vertical surfaces, the requirement for good impact resistance is best satisfied by the use of horizontal grade laminates.
Types of Door
Two types of door are particularly suitable for cladding with Formica decorative laminate.
1. Hollow Doors
A typical construction consists of a frame of softwood members 33mm - 44mm wide x 25mm - 29mm thick, with a paper card honeycomb in-fill of the same thickness and a cell size of approximately 33mm. No other timber members are used except for short pieces fixed to the inside members where locks are to be fitted, and for framing around apertures.
Skins of plywood are glued to either side of this construction with thermosetting resin adhesive.
Formica decorative laminate is applied in a subsequent pressing operation, again using a thermosetting adhesive.
Hollow core doors provide neither fire nor acoustic insulation.
2. Solid Core Doors
These consist of in-fills of cork, flaxboard or chipboard (or a glued stave and block construction), framed all round with glued timber members, and sanded flush.
3mm - 4mm plywood is glued to either side of this core with thermosetting resin adhesive.
Formica decorative laminate is bonded with thermosetting adhesive in a subsequent pressing operation.
Solid doors can be used to provide both acoustic and thermal insulation and certain constructions can provide 1/2-hour and 1-hour fire resistance.
Semi-solid doors, where the surface skins are supported only by vertical or horizontal members spaced at intervals, are unsuitable for surfacing with Formica decorative laminate because of possible show-through of the framework.
Adhesives
The adhesives used throughout should be of at least EN 204 D3 quality.
Lippings
Solid hardwood lippings, typically 9mm thick, are often glued to the edges of doors (using thermosetting adhesives) to provide an attractive and durable finish.
Lippings can be fixed either before the application of the laminate (pre-lipping), or in a subsequent operation (post-lipping).
Glazing Apertures
Where openings are cut into either solid or hollow core doors, radius the internal corners smoothly (minimum 5mm radius) to prevent stress cracking, and shape glazing beads accordingly.
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