Existing wall surfaces are generally unsuitable for the direct application of Formica® decorative laminates. Walls normally need preliminary lining with a good quality plywood or hardboard, well fixed back with masonry nails or screws.
Preparing the Wall
On brickwork and similar rough surfaces, or where pipes run down the wall, fit out the entire wall surface with a groundwork of prepared timber battens, of a minimum 22mm thickness, or prefabricated framed grounds. Allow a maximum span between centres of 400mm. Erect the battens true and aligned, with horizontal grounds at the top and bottom to receive the edges of the panels.
Nail or screw lining material to the grounds. This lining can be chipboard or plywood of not less than 9mm thickness. Include cross nogging-pieces at 600mm centres so that the lining does not yield between the battens when firm pressure is applied to achieve a good bond with contact adhesive. For the same reason, support the timber battens well with packing pieces at fairly close centres. Sand flush all joints in the lining; these should not coincide with the joints in the laminate.
Preparing the Laminate
Whenever possible, store laminate in the conditions in which it will be installed. Laminates generally take two to three days to reach equilibrium with their surroundings. The quickest way to achieve equilibrium is to place the laminate sheets on site with air reaching the backs as well as the fronts.
Before applying adhesive, provide some means of positioning the laminate, such as nails fixed to the bottom of the lining, or blocks of wood of the required height laid on the floor. Then offer the sheet of laminate up to the wall to check positioning.
Applying the Adhesive
Spread the adhesive evenly, first to the back of the laminate and then to the prepared wall surface. Se spreaders help to even the thickness of adhesive.
With brushable contact adhesives, take care to put sufficient thickness of adhesive on the surfaces. On the other hand, too much adhesive can result in entrapped solvents which weaken the final bond.
Allow the adhesive sufficient time to dry to the correct tack-level. This time varies according to temperature and humidity conditions. A useful test is to apply a small piece of brown paper to the glued surface; when the paper does not stick, the surface is ready for bonding.
Never use contact adhesives under conditions of high humidity or very low temperature.
Applying the Laminate
Offer the laminate panel into position; do not allow the two surfaces to come into contact before the sheet is properly aligned. One method is to insert a large sheet of brown paper between the laminate and wall lining. Pull this out when the laminate is ready to be pressed home.
Start by pressing down one edge, then work away from this edge across the sheet, making sure that no air is trapped underneath. With a heavy-duty hand roller, apply as much pressure as possible over the entire surface. Alternatively, use a block of softwood and a hammer.
Allow expansion gaps between each sheet. The easiest way to do this is with panel pins tacked temporarily, 400mm apart, along the vertical edge of the sheet which is already in position. To improve the appearance of this gap, bevel and polish the edges of the laminate. If the gap is to be filled flush, do not use hard-setting sealant.
Panels must be no wider than 600mm; it is easier to handle and apply narrower panels of, say, 400mm width. With woodgrains this can be used to simulate planking.
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