Doors are manufactured of properly cut steel profiles that are connected to make a frame. On request, extra horizontal or vertical crossbars may be added. The elements are connected by welding. Cavities between profiles commonly are fitted with fireproof glass or opaque panels, such as GKF panels (minimum width 12.5 mm), on both sides covered with 1 mm steel sheets. The inswing version of the door is also available: in this case the strips holding the glass are on the same side of the door as the hinges.
The doorframe is made of enclosed steel profile fastened to the masonry with expansion bolts. A cavity between the wall and the frame is filled with mineral wool covered with stucco.
A glass pane is fitted into a properly shaped profile and pressed in place using special strips. Ceramic gasket is fitted between the glass and steel elements (in the place of fastening). Glazing units can also be used, but in this case one of the glasses in the unit should be fireproof.
Steel profiles used for door and doorframe manufacture have special grooves to fit rubber strips. Gaskets provide airtightening and reduce noise made by closing doors. Optionally, a threshold gasket or automatic blocking plate can be used to prevent the smoke spread.
Hinges are made of steel and are fastened to the door assembly by welding. Two hinges are normally used for standard sized door. The doors are powder painted in RAL colour (at the customer’s choice).