Walls can be lined with standard grade MDF in its simplest form by nailing 6 to 12 mm thickness MDF sheets to solid wood studs at 300 to 500 mm centres. For the best results the sheets should be preconditioned in the room for a few days before fixing as any absorption of water from the surrounding air after fixing may result in bowing. Additionally, as a safeguard, expansion gaps up to 2.5mm per metre run should be left between panels to absorb any transverse swelling as a result of an increase in moisture content during any periods of high relative humidity. The surfaces of the MDF can be painted or covered with wall paper. A more decorative effect can be achieved using embossed MDF for paint finishing.
MDF sheets pre-surfaced with wood veneer or decorative foil are also available for wall cladding. The finished surfaces may be further enhanced by grooving to create a random width plank effect.
Another wall and ceiling lining system is based on the use of 12mm MDF cut into 100 mm wide strips with tongue and groove edges. The strips which are supplied pre-painted or with a wood veneer finish are concealed nailed to supporting battens laid vertically or horizontally according to the design requirements for the room. A few days preconditioning of the strips in the room before fixing is recommended to equalise moisture contents.
As an extension to this system, MDF has been used effectively in the form of tiles which were cut and scribed on site to fit in a large archway. The decorative effect was enhanced by hand spraying the individual tiles with different shades of stone effect lacquer to blend in with the natural terracotta shades of the original sandstone materials. The finished tiles were bonded onto a solid substrate using a combination of hot glue for instant adhesion and water-based adhesive for long term durability.
MDF was selected for this application largely because of the ease of shaping the tiles on site and the high quality paint finish achieved on the flat surfaces and bevelled edges with minimum substrate preparation.
Companies with special finishing skills are reporting an increasing interest in the varied metallic, pearl, stone and marble effects that can be achieved on MDF panelling for fitting in cinemas, museums, offices, restaurants and shops.
MDF can be used as an alternative for traditional panelling constructed with solid wood framing enclosing solid wood centre panels which may be flat, raised or carved. The framing pieces can be manufactured from wood veneer wrapped MDF mouldings corner jointed with tongues or dowels. The centre panels, fixed in grooves or rebates in the frames, can be flat pressed wood veneered MDF or membrane pressed wood veneer on a raised MDF panel. A more decorative finish can be achieved using deep embossed MDF centre panels or carved panels machined using a CNC router.
Apart from considerations of lower cost, the main advantage of MDF based panelling over solid wood is the reduced risk of centre panel shrinkage or joint opening due to changes in ambient conditions.
When selecting MDF for any wall panelling applications, note should be taken of any national or local regulations relating to the use of flame retardant materials. Particular attention should be given to the choice of finishing treatment to maintain the flame retardant characteristics of the underlying board.