The foaming of the door frame.
What gap is needed between door, floor and frame : The Foaming Of The Door Frame.
Quote from Article entitled What gap is needed between door, floor and frame:
Between a leaf of interior doors and the floor it is required to leave a gap of at least 2 – 2.5 cm to provide natural ventilation. A gap of 4 cm is allowed for convenient and safe door opening.
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