Ah the need to keep abreast of everything that changes to keep us relevant. Recently I was involved in an exercise in that as I attended a webinar courtesy of Milwaukee CSI and AWI – Architectural Woodwork Institute on the newly developed ANSI/AWI 0641-2019, Architectural Wood Casework, presented by Doug Hague AWI, EVP.
I was sad to hear that AWI, WI and AWMAC were not continuing with the comprehensive Architectural Working Standards manual. But given that they wanted to make a fundamental change in the structure of the standards I could see why the move was warranted and the three organizations couldn’t come to an agreement to continue with one document. That change was to move from the proscriptive standards that they had proffered for many years to a performance-based one. This presentation clearly explained the nature of that change and how it will fundamentally modify my specifications once I incorporate the necessary language.
So instead of saying “Use 3/4-inch thick veneer plywood for cabinet boxes and frames.” It now refers to their very familiar Grades of Economy, Custom or Premium, coupled with new Duty Levels of 1, 2, 3, and 4. The grades which used to encompass both aesthetic concerns of fit and appearance, and the prescriptive requirements of how a cabinet was put together and with what materials; are now just relegated to the aesthetics of the cabinet while the functional and structural aspects are dealt with under the Duty Levels.
Duty Levels are based on testing standards of five individual components, Base Cabinets, Wall Cabinets, Tall Cabinets, Drawer Boxes and Shelf Support. The Duty Level roughly correspond to the product’s expected nominal use such as 1 – Light Commercial, 2 – Commercial, 3 – Institutional, 4 – Laboratory. There are two testing criteria methods of applied loads to an uniform assembled cabinet unit. In the first methodology, Assembled Unit, weight bags are applied, a DL-1 base cabinet has 45 lbs. per sq. ft. applied to the top, 25 lbs. per sq. ft. to an adjustable shelf; a DL-3 has 90 lbs. per sq. ft. applied to the top and 50 lbs. per sq. ft. loaded onto the adjustable shelf. For all 4 Duty Levels the door and drawer loads are the same across designations as 100 lbs. hanging on the doors and 50 lbs. placed in each drawer. In the Structural Integrity Methodology, a pneumatic press is used to apply 135 to 260 lbs. per sq. ft. across the top of the cabinet. These are arbitrary loads for relative strength values and are not expected loads that should be considered normal or expected to be sustained by the cabinet.
Shelving values are based on using a metal L-shaped pin rest support and relies on known Modulus of Elasticity values from 400,000 to 1,800,000 psi of the shelf material and corresponding dimensions.
So, for the engineers among us, this brings a degree of measurable objectivity to establishing quality requirements, but it removed the easier review of shop drawings against a written value of thickness, material type, etc. However, this now allows a cabinet manufacturer to provide a cabinet box of equal performance over a broad range of construction techniques and materials. So instead of relying on stating that boxes and end panels must be constructed of veneer plywood versus melamine-clad MDF to establish a sense of quality, requiring a Duty Level 3 (default value if nothing is stated), one manufacturer can create the veneer sheet box while another the MDF and take advantage of whatever price benefits they are able to use with the system that they prefer or typically produce.
With this dual grade designation system, the architect can easily assign a high aesthetic quality with a low performance grade to a lobby or boardroom cabinet that will have very light use, while stating a separate designation for a back-of-house work-counter-cabinets with an Economy grade appearance but a Duty Level 4 performance rating. Adjusting the cost of manufacturing to fit the cabinet and use and not applying the same cost to all cabinets I see this in turn may require use a schedule to clearly designate location, cabinet type, Grade, and Duty Level either on the Drawings or in the Specifications.
Another point of note is that AWI now uses a soft-conversion metric measurements as the predominant system with English values in parentheses. Given that the U.S. is the only major country in the world clinging to English measurements, this is one more notch on the acknowledgement we live in a global marketplace requiring a more standardized, accurate, less prone to error, and recognized measuring system. In case you wondered, Liberia and Myanmar are the only two other hold-outs, what great company. Perhaps someday metric will become the norm, but unfortunately, I sincerely doubt it given that state of American psyche today which is even more divided and America-centric.
An interesting side note. There was a slide showing the strength comparisons of drawer boxes using plywood, MDF, particle board and solid lumber with various joint configurations. The age-old concept that a solid wood, dovetailed drawer box is the strongest among the options available was clearly shown not to be so. AWI tested 5 boxes of each type and found that several other combinations performed much better than the solid wood-dovetailed version. The best was a particle board miterfold joint, followed by veneer core plywood and dowel screws. The miterfold was a new joint for me. I was familiar with the shoulder miter, but it seems that saw blade manufacturers have produced a dado blade which cuts a similar shaped joint in one pass of the sheet material but leaves the last millimeter of veneer or melamine uncut, assuming you have the blade height set correctly, so that the carpenter glues, gently folds and clamps the routed sheet together to make the corner. Slick!!
To access the standards, one for Finish Carpentry and Installation and one for Casework, you can freely access the text at www.awinet.org but it’s only accessible by individual section which I found navigating is a little cumbersome as I tired to navigate between sections to see what content was placed in each, but with time and familiarity I’m sure it will become second nature. The full standard is available from AWI, ANSI or other standards print house for cost.
A key aspect of the new format and its use is the reliance on cabinet shops that know or understand the basic construction required to achieve the various Duty Levels. I can image that a shop that is not as aware of, or compliant with the performance criteria could have a harder time meeting the project’s specifications and what is expected by the architect. The architect will have to be more diligent on receiving manufacturer qualification statements and reviewing the shop drawings to see if they use this new standard and are in compliance and not just passing off their standard cabinet as the requested Duty Level.
I hope you found this helpful, enlightening, or at least not a total waste of your time. Thank you for taking the time to read my thoughts as I start my life as Blogger. If you have any further thoughts or questions on this topic, please feel free to contact me. I’m constantly learning and though I try and be as thorough as possible on my subjects there is always something else to be considered from which we may change our position and learn together.