Buyers & specifiers guide to particleboard & MDF.
Today's particleboard provides industrial users the high, consistent quality and range of design flexibility needed for fast, efficient production lines and high-quality products that consumers require.
Particleboard is a wood panel product consisting of wood particles of various sizes that are bonded together with a synthetic resin or binder under heat and pressure. Particle geometry, resin levels, board density, and manufacturing processes may be modified to produce products suitable for specific end uses. At the time of manufacture, additives can be incorporated to provide greater dimensional stability, better fire resistance, or improve other properties.
The recovery and use of residual wood in the manufacture of particleboard helps make optimal use of our forest resources.
The American National Standard for Particleboard, ANSI A208.1, which classifies particleboard by the density and class, is the voluntary particleboard standard for the industry. This standard, which covers physical, mechanical and dimensional characteristics as well as formaldehyde levels, was developed through the efforts of the National Particleboard Association (NPA), producers, users and general interest groups. Copies of the ANSI Standard may be obtained from the NPA.
Particleboard Interior Applications
Grade Product (ANSI References A208.1)
Floor M-1 ICBO, SBCCI, BOCA, Underlayment One-and Two-Family Dwelling Code
Manufactured D-2 HUD-Manufactured Home Decking D-3 Home Construction and Safety Standards
Shelving M-1 M-2 M-3
Countertops M-2 ANSI A161.2 M-3
Kitchen Cabinets M-S ANSI A161.1 M-2
Door Core LD-1 NWWWDA Industry LD-2 Standard Series I.S. 1-87 (Wood Flush Doors)
Stair Treads M-3 HUD/FHA UM 70a
Mouldings M-3 WWMMP Standard WM 2-73
FORMALDEHYDE EMISSION LIMITS
Formaldehyde emission limits are set for particleboard in ANSI Standard A208.1. This standard includes separate emission limits for industrial particleboard (0.30 ppm) and particleboard flooring (0.20 ppm). These limits are based on a product loading of 0.425 square meters per cubic meter (0.13 [ft.sup.2]/[ft.sup.3]) of room volume.
(NOTE: This loading reflects the use of particleboard as floor decking in a manufactured home. Additional information regarding formaldehyde emission test methods is available from the NPA.)
Over the past several years, industrial grade particleboard has been recognized throughout the wood industry as an ideal substrate for laminated panel constructions, utilizing various types of overlay surfacing materials. Particleboard is favored by laminators because of its uniform density, thickness tolerance, and surface smoothness. Other board properties such as dimensional stability, strength, stiffness, flatness, screw-holding power, and workability contribute significantly to ease of fabrication and ultimate performance of the end product.
High-pressure laminates, thermo-fused, resin-saturated papers, vinyl films, hot transfer films, decorative papers, and wood veneers comprise the types of overlay materials most commonly applied to particleboard substrates by laminators.
Industrial products used in kitchen cabinets, office and residential furniture, case goods and other demanding applications are typically ANSI A208.1 M-S, M-2, or M-3.
Most kitchen cabinets manufactured today use particleboard for shelves, sides, backs, drawers, doors and other parts because of its demonstrated superiority and economic advantages. Particleboard grades M-5, M-2, and M-3 as described in ANSI A208.1 are usually used in kitchen and vanity cabinets. ANSI Standard A161.1 RECOMMENDED PERFORMANCE AND CONSTRUCTION STANDARD FOR KITCHEN AND VANITY CABINETS is sponsored by the Kitchen Cabinet Manufacturers Association (703-264-1690).
The inherent particleboard qualities-stability, flatness, smoothness, no knots or voids, high impact strength and ease of laminating-make it the major core-stock material for countertops, meeting the ANSI A161.2 standard for performance of laminated countertops sponsored by The Decorative Laminate Products Association.
A widely used application for particleboard in construction is floor underlayment. It is dimensionally stable, flat, without voids, and comes in convenient 4[feet] x 8[feet] panels for easy installation.
Particleboard floor underlayment when combined with a sub-floor provides a strong, stiff floor and offers the additional advantages of excellent acoustical properties, increased insulation values, and outstanding impact resistance. Particleboard floor underlayment may be installed with nails or staples, (or a combination of glue and nails for stronger, stiffer floors) and covered with carpeting, resilient tile, or seamless floor coverings.
It is accepted for use in construction by FHA or VA insured mortgage packages for single and multi-family homes. Panels bearing the NPA grademark indicate the underlayment was manufactured to meet ANSI Standard A208.1. Particleboard floor underlayment is also referenced by ICBO, SBCCI, and BOCA.
MANUFACTURED HOME DECKING
Particleboard Manufactured Home Decking (MHD) comes in thicknesses between 5/8[inches] and 13/16[inches], square edge and T&G and in specified lengths and widths. MHD is accepted as a design standard by HUD for inclusion in the HUD Manufactured Home Construction and Safety Standards. MHD is also defined in ANSI A208.1 and is available in two grades, D2 and D3.
HUD requires MHD to have formaldehyde emissions at below 0.30 ppm. MHD products manufactured to comply with ANSI A208.1 have formaldehyde emissions at below 0.20 ppm and meet the HUD requirement.
Look for the NPA Grademark on MHD manufactured to meet this standard.
Particleboard is an excellent material for interior stair treads. It will not split, has no knots or grain, and comes in a variety of lengths to minimize waste. Particleboard stair treads are manufactured to a uniform thickness and are bullnosed on one edge for time saving convenience. Physical properties for particleboard stair treads are specified by ANSI A208.1, Grade M-3.
Use of particleboard stair treads is described in the HUD/FHA Use of Materials Bulletin 70a. Spans of up to 42[inches] between risers are allowed. Installation requirements include the use of either carpet or resilient flooring coverings. Additional information on particleboard stair treads is available from the NPA.
Particleboard shelving is a popular application that provides the builder with an economic, flat, easy to cut, void-free, smooth surface. Industrial grades are typically used depending on particular requirements. Particleboard shelving comes plain or edge filled with a square edge or bullnose. Shelves are usually designed for fairly specific applications, e.g., closets, kitchen cabinets, bookcases, etc. with assumed typical loads. For example, kitchen shelves are designed for a uniform load of 15 psf; closets, 25 psf; bookshelves, 40 psf. To determine any uniform load, divide the expected load (in pounds) by the square footage of the shelf.
DOOR CORE, JAMBS, & MOULDINGS
Doors made with particleboard door cores have unique advantages not found with other materials. Particleboard door core is warp resistant, solid, with no knots or voids. The remarkable insulation values and sound resistance of particleboard door core assist in limiting heat loss and transfer of sound waves. It is referenced in the National Wood Window and Door Association I.S. 1 Industry Standard and its physical properties are specified in Grades LD-1 and LD-2 in ANSI A208.1.
Door jambs made from particleboard - vinyl wrapped or ready for painting - have gained increased acceptance as an economic package for builders.
Particleboard is recognized as a substrate in WM 2-82, the industry standard for vinyl wrapped interior moulding and millwork, published by the Wood Moulding and Millwork Producers Association (916-661-9591). Medium Density Fiberboard (MDF) is a product used increasingly in the manufacture of kitchen cabinets, furniture, door parts, mouldings, and millwork. Panels can be made in a variety of sizes and density, thus providing great opportunity to design the ultimate product with the specific MDF needed.
The surface of MDF is flat, smooth, uniform, dense and free of knots and grain patterns. All of which make finishing operations easier and consistent, especially for demanding uses such as direct printing and thin laminates. The homogeneous edge of MDF allows intricate and precise machining and finishing techniques for superior finished products, such as stereo cabinets, relieved door fronts and mouldings. Trim waste is significantly reduced when using MDF compared to other substrates. Improved stability and strength are important assets of MDF with stability contributing to holding precise tolerances in accurately cut parts. It is an excellent substitute for solid wood in many interior applications. Through technical sales and service and research and development, new uses for MDF are constantly being identified.
Medium Density Fiberboard (MDF) is a generic term for a panel primarily composed of lignocellulosic fibers combined with a synthetic resin or other suitable bonding system and bonded together under heat and pressure. Additives may be introduced during manufacturing to improve certain properties.
The recovery and use of residual wood in the manufacture of MDF helps make optimal use of our forest resources.
ANSI Standard A208.2, Medium Density Fiberboard is the industry standard for MDF. This standard classifies MDF by density and use (interior or exterior) and identifies four interior product grades. Specifications identified in the Standard include physical and mechanical properties, dimensional tolerances and formaldehyde emission limits. Specifications are presented in both metric and inch-pound units. Copies of this standard are available from the NPA.
FORMALDEHYDE EMISSION LIMITS
ANSI A208.2 sets the formaldehyde emission limit for MDF at 0.30 ppm at a loading of 0.26m2/m3 (0.08 [ft.sup.2]/[ft.sup.3]). MDF is used primarily as a fabricated and finished product in furniture, fixtures and cabinetry. The addition of finishes or overlays may significantly alter product emissions.
Additional information regarding formaldehyde emission test methods is available from the NPA.
Cabinet manufacturers use MDF when they want a superior cabinet and require a smooth, defect-free panel, side, shelf, or other printed or wrapped surface.
Custom cabinet shops prefer to work with it because of the advantages of its tight edge and the ease of routing and sawing for clean, sharp lines, and shaped edges.
MDF is used as a core material for paneling with veneers, printed surfaces, vinyl and low pressure laminates. It is stable, flat, smooth, does not telegraph and the panels can be installed quickly and easily.
DOORS, JAMBS, MILLWORK
MDF is a superior product for these applications because of its warp resistance, smoothness and insulating qualities. It is recommended for baseboards, door jambs, casings, stiles, rails, hollow core doors and trim. It is referenced in NWWDA Industry Standard I.S. 1 Series for Wood Flush Doors, for use as a stile, rail or lock block material for hollow core doors.
LAMINATING AND FINISHING MDF
MDF has become a premier substrate for expensive veneer, thin vinyls, hot transfer foils and low pressure, resin-saturated papers. This has been due primarily to its smooth surface and edge-finishing qualities. MDF's work ability, good dimensional stability, flatness, close tolerances, dent resistance, lower glue usage, and lack of grain-telegraphing have contributed to its wide acceptance. Good bond strength, screw-holding, and resistance to compression and warp make MDF an ideal substrate.
MDF is easily shaped into almost any form and is commonly available in lengths up to 20 feet. Because of this MDF is an excellent material for vinyl and paper wrapped as well as directly finished interior mouldings.
EDGE SHAPING AND MACHINING
One of the prime features of MDF is its sharp, clean edge-machining with minimal treatment prior to finishing. Edge-banding or mouldings are eliminated with the right finishes.
With the proper selection of equipment and cutting tools, MDF can be machined into intricate patterns as easily as natural wood. The homogeneous nature of MDF results in clean, sharp reproduction of designs free from fuzzing or chip-out, provided properly designed carbide or diamond tools are used.
Furniture manufacturers are using "embossing"-pressing cast die patterns into the MDF surface-to produce three-dimensional designs. MDF's even texture and consistent properties make it an excellent material for embossing.
|Printer friendly Cite/link Email Feedback|
|Title Annotation:||medium-density fiberboard|
|Publication:||Wood & Wood Products|
|Article Type:||Buyers Guide|
|Date:||Jan 1, 1996|
|Previous Article:||Panel makers upgrade plants to meet demand.|
|Next Article:||The best solution at the lowest cost - not a machine.|