Frameless Glass Doors
Summary
Frameless glass doors are 1/2 in. or 3/4 in. fully tempered glass leaves with no stiles, held at top and bottom by patch fittings or rails and swung on pivots, floor closers, or overhead concealed closers. They give maximum transparency at lobbies and tenant fronts, but glass prep, floor closer pockets, and hardware limits must be coordinated before fabrication.
Cols
Terminology
- Patch fitting: clamp-on corner fitting at top and bottom of the leaf that carries the pivot
- Door rail: continuous metal channel at top and bottom, or bottom only; carries pivots and lock
- Floor closer (floor spring): closer recessed in a floor box below the pivot point
- Overhead concealed closer (OHCC): closer recessed in the header above the door
- Pivot setback: distance from the door edge to the pivot center; 2-9/16 in. to 2-3/4 in. typical
- Transom patch / sidelite patch: fittings connecting the door header to fixed glass panels
- Header: metal channel or glass transom above the door holding the top pivot
- Lock patch / bottom rail lock: lock housing on a fitting or rail engaging a floor or jamb strike
- Swing-free pivot: pivot without closer; door returns only by hand
- Butt glazed: glass-to-glass joints sealed with silicone or gasket, no mullion
- Fully tempered (FT): heat-treated glass meeting ASTM C1048 and safety glazing tests
Standards
Sizes
- Glass thickness: 1/2 in. standard for doors; 3/4 in. for tall, wide, or heavy-traffic doors; 3/8 in. for light interior
- Patch fitting doors: up to about 42 in. wide by 102 in. tall and 176 to 194 lb per manufacturer limits; larger doors need full rails
- Rail doors: taller and wider leaves possible; rails 2-1/2 in. to 10 in. tall
- Clear opening is reduced by pivot setback and pull projection; check against the required clear width
Safety glazing
- Fully tempered door glass is tested to CPSC 16 CFR 1201 impact categories and ANSI Z97.1
- Permanent etched safety glazing label on each lite
Test standards
- ASTM C1048: heat-treated flat glass
- ASTM C1036: flat glass substrate
- ANSI/BHMA A156.4: door controls, including floor and overhead concealed closers
- ANSI/BHMA A156.3: exit devices, including rail-mounted glass door devices
Materials
- Glass: clear, low-iron, tinted, or acid-etched tempered glass; laminated only with fittings rated for laminated glass
- Fittings and rails: satin or polished stainless steel, satin anodized aluminum, bronze, or powder coat
- Floor closers: cast iron or steel box, set in a recessed pocket in the slab
- Pulls: back-to-back ladder or ring pulls through drilled holes
- Exit devices: rail-mounted or glass-mounted push bars where panic hardware is required
Uses
Specific uses
- Building lobbies and hospitality entrances
- Tenant suite and conference room fronts in office interiors
- Retail fronts in malls and street-level shops
- Showroom, gallery, and museum entries
- Interior entrances paired with butt-glazed sidelites and transoms
Pros and cons
Pros
- Minimal sightlines and maximum transparency
- Clean detailing with glass sidelites and transoms
- Durable stainless hardware with long service life
- Easy to clean and refinish
Cons
- Floor closers need slab recesses and coordination with structure, waterproofing, and radiant floors
- Limited locking, access control, and exit device options without rails
- No thermal break or air seal; poor energy performance at exterior openings
- Not fire-rated
- Heavy leaves strain pivots; glass breakage requires full leaf replacement with long lead time
Manufacturing and cost
Construction
- Glass cut, edged, drilled, and notched for fittings and pulls before tempering; no field cutting after tempering
- Fittings clamp to the glass with gaskets and set screws; rails are wet or dry glazed
- Floor closer box set in a slab pocket, leveled and grouted before finish flooring
- Header anchored to structure above; transom and sidelite glass set in shoe or channel glazing
Main manufacturers and suppliers
Trade association: National Glass Association.
Typical costs
- Single patch fitting door, 1/2 in. tempered, with floor closer and pulls, material only: $2,000 to $4,000
- Installed single door with header and standard hardware: $3,000 to $6,000
- Installed pair with sidelites and transom: $8,000 to $15,000
- 3/4 in. glass, low-iron glass, rail locks, and electrified hardware add to these ranges
Sources
- C.R. Laurence: bottom door patch fitting specifications, https://www.crlaurence.com/p/PH10DBR
- Glass Experts: dormakaba bottom patch fitting for 3/4 in. glass, https://shop.glassexperts.com/en/dormakabaa-bottom-door-patch-fittings-with-bottom-inserts/14566-dormakabaa-brushed-stainless-bottom-door-patch-fitting-with-bottom-insert-for-3-4-glass.html
- GPO: 16 CFR 1201.2 safety standard for architectural glazing materials, https://www.gpo.gov/fdsys/pkg/CFR-2014-title16-vol2/pdf/CFR-2014-title16-vol2-sec1201-2.pdf
- I Dig Hardware: what is safety glazing, https://idighardware.com/?p=14069
- Corada: 2010 ADA Standards Section 404 doors, https://www.corada.com/documents/2010ADAStandards/404
- Sweets: 08 00 00 openings, https://sweets.construction.com/masterformat/companies/08-00-00-openings
- Wikimedia Commons: Cleaning the glass door at Café Reconcile New Orleans 20230216-FNS-CDP-0332.jpg, by U.S. Department of Agriculture (Public domain), https://commons.wikimedia.org/wiki/File:Cleaning_the_glass_door_at_Café_Reconcile_New_Orleans_20230216-FNS-CDP-0332.jpg