Demountable wall systems, also called movable walls, are incredible solutions for creating flexible enclosed environments that can adapt over time. With these products come a number of terms that you may or may not be familiar with. We created this handy glossary of terms to help you better understand the nuances of these solutions and converse more easily with your general contractor, architect, designer or vendor!

  • Back-painted glass
    Back painted glass is any form of clear glass that is painted from the back side and viewed from the front side. It is commonly used to create colored glass walls and glass markerboards.
  • Butt glazing
    An installation where the glass is joined without structural support on the vertical edges. Butt glazing is used to create larger uninterrupted spans of glass for an elegant, streamlined aesthetic.
  • Clerestory
    Clerestory refers to a horizontal segment of glass above a door, in lieu of having a door that runs the full height of the wall.
  • Closers
    Automatic device to close or hold open a door. These can be visible, concealed, overhead or in the floor. Closers are typically required for doors with security hardware.
  • Cornice Height
    Cornice height refers to free-standing, self-supporting walls with no attachment to the ceiling. Typically 18″ below the existing ceiling will meet code requirements. The benefit to these is they are less invasive meaning you often won’t need to relocate a sprinkler of ventilation system, however this solution offers little sound privacy as there is no true ceiling present.
  • Demising Wall
    Demising walls can be drywall or demountable. This refers to a wall between two or more offices that do not contain a door and typically house equipment such as power, AV, and whiteboards.
  • Double glazed
    Two pieces of glass separated by a vacuum. Double glazing offers superior acoustics for enclosed spaces.
  • Drop Seal
    Mechanism concealed under door or applied to either side that engages upon door closing. Provides seal to outdoor environment for increased acoustical performance.
  • Electric Strike
    Small electro-mechanical device that holds the door secure by the strike bolt. Once credentials are authenticated, the latch is allowed to open one time and the bolt is recaptured and locked once the door is return to the closed position.
  • Extrusion
    Extrusion refers to the aluminum tracks that house the glass and doors. Aluminum billets are forced through a die under immense heat and pressure to create the extrusion, which is further processed and powder coated or anodized before shipping.
  • Glass fronts
    Modular glass walls on one side of an enclosed space, used in combination with solid demountable wall panels on the other sides, or traditional drywall. Glass fronts can be more cost effective than traditional glazing.
  • Laminated glass
    Laminated glass has an interlayer between its two or more layers – typically polyvinyl butyral (PVB) or ethylense-vinyl acetate (EVA). This interlayer holds it together when shattered, as well as offers additional acoustical benefits.
  • Lever/Ladder Pulls
    Lever sets can be either cylindrical or mortice. A mortice set appears built into the door where a cylindrical handset has a round ring and appears applied to the door. A ladder pull/barn door pull is a vertical handle typically applied through the door.
  • Linear foot
    A 12-inch measurement of length in a straight line. When specifying demountable walls, the number of linear feet is calculated rather than cubic feet.
  • Low Iron Glass (Starfire Glass)
    Low iron or Starfire™ glass is a true clear glass that appears as a clear to very slight light blue tint at some angles but is only distinctly noticeable when viewed side by side or to the trained eye. This is different from clear glass which is the standard glass, and has a blue/green tint.
  • Mag Lock
    A mag lock is an electro-mechanical device mounted to a door and door frame. The device holds a door secure until the proper credentials are provided to allow access.
  • Modular walls
    Modular wall systems are stick-built from parts and pieces and are fully assembled on site. Installation requires more labor and coordination than unitized systems, but they offer a greater variety of specification options. Modular walls are often designed parametrically.
  • Mullion
    A mullion is a structural member that can also support horizontal mullions. Mullions carry weight and support walls.
  • Muntin
    Muntins (often confused for mullions) are applied, non-structural decorations meant to divide up the glass. They are purely a design choice and can be applied horizontally, vertically, or diagonally.
  • Panic Hardware
    Panic hardware is typically a special application. It is required in higher traffic areas or the path of egress from the building. This is typically a push to release type of operation and bypasses any security measures in the event of an emergency.
  • Parametric
    Parametric sizing is the ability to change dimensions of a product within pre-engineered limits. Sizes can be specified to 1/32nd of an inch, allowing for virtually any size to be ordered. Parametric sizing reduces the need to place orders through special order, leading to a decrease in order processing time, immediate availability of pricing, and an overall cost savings for the customer.
  • Pivot Doors
    Pivot doors are attached to ball bearings on the top and bottom of the door only.
  • Profile
    The profile refers to the height of the base trim, typically between 7/8” and 4”. Lower profiles create more open and transparent aesthetics.
  • Seals
    Seals refer to the gaskets that seal all the nooks and crannies where sound can escape.
  • Sidelight
    A sidelight is a narrow vertical window that flanks a door or a larger window.
  • Single glazed
    Glass that is made up of a single pane.
  • Skin
    A skin is an outer surface that is applied to the frame of a demountable wall. Because skins are separate from the structure, they can be segmented differently on opposite sides of the wall. Skins can be removed and changed out for another material. A skin can be painted steel, fabric-wrapped steel, laminate, veneer, wood, ceramic whiteboard, etc.
  • Slider Doors
    Slider doors are opened and closed laterally or in line with the wall. They encroach less real estate than a swing type door.
  • Specialty Glass
    These include switch glass, tinted glass, art glass, frit glass, back painted glass, curved glass, mitered corners, and various films including Casper Cloaking™.
  • STC
    STC stands for Sound Transmission Class, which rates how much sound a wall or barrier will stop.

    • For spaces where privacy is desired but the sensitivity of information is not an issue, STC ratings of 25-35 are recommended. Single and double-glazed glass walls are options for this level of privacy.
    • For spaces where privacy and the sensitivity of conversations is of high concern, STC of 40-52 is ideal. Solid wall panels, alone or in combination with double-glazed glass walls are the best option.
    • Here are some example ratings:
      25        Normal speech easily understood
      30        Normal speech audible, but unintelligible
      35        Loud speech audible and understandable
      38        Normal speech inaudible, loud speech audible, but not understandable
      40        Loud speech audible, but unintelligible
      45        Loud speech barely audible
      50        Shouting barely audible
      55        Shouting not audible
  • Swing Door
    Swing doors are hinge mounted and attach along the heel of the door or through the door itself in glass applications.
  • Switch Glass
    Switch glass is a specialty laminated glass product that has a layer of proprietary film sandwiched between the panes that is normally frosted and turns opaque when voltage is applied.
  • Tempered glass
    Tempered glass fractures into small, relatively harmless pieces when shattered. It is about four times stronger than regular glass.
  • Transom
    A transom is a transverse horizontal structural beam or bar, or a crosspiece separating a door from a window above it.
  • Unitized walls
    Unitized wall systems are pre-assembled as a unit prior to delivery on site for installation. Installation and reconfiguration is typically very quick and requires less labor than modular wall systems.

We hope this glossary is helpful as you compare demountable wall systems!