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Exterior Steel Frame Glass Door Construction

Glass Divided Lites

A lite refers to each separately framed piece of glass on a window or door. A mullion is the line that forms a division in a window or door and this division can either be a real, or simulated.

True Divided Lites(TDL): the glass on the window isn't a single piece, but multiple pieces separated by mullions that go through the glass.

Simulated Divided Lites (SDL): the glass is a large, single piece with mullions placed on top of the glass, but they don’t cut through it.

True Divided Lites

True Divided Lites - TDL

  • Easy to maintain and clean; if a piece of the unit is damaged, you can easily repair it without affecting the rest of the lites
  • Structurally has more strength due to more bars stabilizing the window
  • High-end look. Width: 1-5/8".
Simulated Divided Lites

Simulated Divided Lites - SDL

  • Most cost-effective
  • Gives a similar appearance to TDL
  • SDL allow narrower width in mullions: 3.4".

Exterior Steel Door Profiles

Flat-to-Flat TDL

TDL Flat-to-Flat

Flat-to-Angled-Shape TDL

TDL Flat-to-Angled-Shape

Flat-to-T-Shape TDL

TDL Flat-to-T-Shape

Flat-to-Flat SDL

SDL Flat-to-Flat

Flat-to-Triangle SDL

SDL Flat-to-Triangle

Flat-to-T-Shape SDL

SDL Flat-to-T-Shape




We use Door Hardware with Euro Multipoint

  • Always offered with our European multipoint locking mechanism
  • Our multipoint is the Secury Europa S R4 from GU
  • This system comes with a distance of 3-5/8" between the keyhole and the lever hole

Multipoint Mechanism

Latch: available for left hand or right hand

Follower: The receiving end of the lever spindle that provides the locking operation.

Deadbolt: Depending on the system, can come as a 1 or 2-turn with a deadbolt throw of 20 mm

Cylinder Hole: Accepts a round or profile cylinder of 22mm in diameter

Exterior Steel Door Corner Sample

FerroFinestra W75 TB

Ottostumm's newest system, W75 TB FerroFinestra, utilizes a palpable, visible insulating surface. This is our most advanced insulator in our steel door collection. The profile of this systems allows us to utilize insulating, low-E glass the increase thermal protection. This insulator is fiberglass-reinforced and provides superior insulating properties for the harshest of climates.

Exterior Steel Door Corner Sample

FerroFinestra W50 TB

The W50 TB FerroFinestra from Ottostumm allows for our steel exterior doors to keep their most authentic form with the overarching effects from the 20th century steel door profiles. The insulator used here is a high-density thermal protector that can be paired with our low-E glass to meet current regulations. This combination provides a sleek style that is fully customizable in a large selection of finishes and designs.


(sold separately)
Steel Door Handle - Steel handrail 20
Steel Door Handle - Steel handrail 20
Steel Door Handle - Steel handrail 20
Steel Door Handle - Steel handrail 20

Please specify in the comments box below if you selected different finish or lever style of the Handle Hardware on