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Attaching Items to the Face of an Operable Wall

Needless to say the decision to incorporate a $10,000 operable wall in a $30,000,000 educational facility is not a big deal. But in fact it is a decision that has resulted from thought and a vision of how the facility will function. It also involves many design professionals before a final selection is made. The School Board/Owner who recognizes the need for flexible space management especially in a multi purpose facility. The Architect & his design team who translate this vision into working drawings & specifications. The Structural engineer who designs a specific structure to support the wall. The acoustician who determines acoustic needs. The Interior designer who decides how the wall will look.

Different needs must be satisfied. The owner wants durability & longevity. The Architect wants products of which he is proud. The maintenance people want ease of movement and as maintenance free as possible. The users want acoustic privacy, flexibility, and multi use options such as write on surfaces, the ability to attach items or project on to the surface, pass doors etc.

Unlike many items in a School the operable wall is a dynamic multi purpose product that can greatly contribute to the success of the overall project. An operable wall is different from static architectural items such as flag poles, lettering, lockers etc, a wall will do many things and accomplish many tasks. It can be a valuable educational tool. Let’s look at 3 components/features of a typical wall and see how they interrelate: durability, acoustics and the ability to attach/fasten items to the panel surface.

As an operable wall is a heavy but easily moved dynamic object it is subject to abuse and damage. It is often relocated by inexperienced people who have no regard for its care requiring that it be built as solid and strong as possible. The area most susceptible to damage and difficult to repair/replace is the panel skin. Many time skin surfaces made with substrates of gypsum board or MDF are specified. Moderco discourages this and highly recommends that all panel skins be manufactured from minimum 24 ga. steel skins over a substrate of gypsum board. Steel is far more resistant to impact loads or damage due to miscellaneous outside forces. The addition of a protective steel skin adds very little to the cost of the panel, especially as it relates to the overall cost of the project and projected maintenance and repair costs if less durable skin materials are accepted.
Acoustic (STC) qualities are typically achieved by combining panel perimeter design (vertical & horizontal seals), panel thickness (typically 3 or 4” thick), panel design (as an example the isolation of skins from panel frames to minimize through transfer of sound) and mass (panel construction usually reflected in weight). Mass or weight is best achieved by adding layers of steel to the panel skins. This is the most economical way and does little to add to the panel thickness. The other factor is to carefully look at the sound test of the wall under consideration. If outside steel was used in attaining the specified manufacturer’s STC value then outside steel should be provided in the supplied product.

Fastening/attaching to the panel face presents a problem. The typical way is to specify & provide a “tackable surface”. This is usually a minimum ¼” thick layer of cork over top of the substrate that satisfies the STC test and then covered with vinyl or simply vinyl covered ½” thick gypsum board into which you can stick tacks. There are several problems with this concept. If you consider cork, ¼” on both sides adds ½”/panel to the stack space required as well as dramatically increasing the panel costs: cork is not inexpensive. Manufacturer’s also have difficulty in applying cork to various panel skins, predictable quality of the raw product and eventual deterioration of the material after years of use. It wears out and disintegrates. Sticking pins into gypsum board is the most common system. But this also eventually results in deterioration of the gypsum board even if special (and more expensive) boards are used.

In both cases the panel covering, even though it is specified as “self healing” will develop holes and fatigue requiring recovering. Often when the vinyl is stripped off of a “tackable” panel it is found that the gypsum is so badly pierced that it also has to be replaced. Both materials require the use of “pins or tacks” that are constantly being lost needing replacement, are sharp and potentially injurious, and often left in panels which could result in damage to adjacent panels if not removed prior to stacking.

In Moderco’s opinion we highly recommend the use of magnets for the purpose of attaching materials to panel faces. By using magnets you will retain the positive features of a durable steel skin, be able to attain higher STC values at very little extra cost, reduce panel skin deterioration (hidden from view), the need to recover will be delayed indefinitely and the overall class room and it’s occupants will be safer as sharp tacks will be removed from the space.

But magnets have other applications as a teaching aid. How many times have you been in a school where the alphabet &/or numbers are displayed on the walls. Magnets in all kinds of sizes and with letters or numbers imprinted on them can be used. Instructors can use these same figures to teach the alphabet or spelling: addition and subtraction etc. You can purchase magnets large enough to write students names on or lessons. Magnets strong enough to use as coat hangars are available. The possibilities are many.

Moderco highly recommends the use of magnets on steel skins rather that using stick pins into soft gypsum board as a means of attaching information to panels. Both durability and tested sound qualities are retained in addition to eliminating the need for those sharp pins in the classroom.

In summary “magnetable skins”:

• Are more durable and impact resistant than “soft “tackable skins.
• Prolong life of the panel system because skins will not deteriorate due to use of pins.
• Allow one to stack panels that use magnets but you cannot if pins are used due to projection.
• Allow items that are attached to be left on when panels are stacked.
• With imagination magnets can be used as teaching aids
• Eliminate the use of sharp dangerous pins.