Polyurethane foam for installation of the door frame.
What gap is needed between door, floor and frame : Polyurethane Foam For Installation Of The Door Frame.
Quote from Article entitled What gap is needed between door, floor and frame:
What gap should be left, when it comes to the standard door leaf by height of 200 cm and by width from 60 to 90 cm? In such cases, it is usual to leave the required gaps by width up to 5 mm. And it is usually sufficient to have 3 mm gaps. It is more effective to leave 4 mm and more for rooms with high humidity and for doors made from materials absorbing well moisture.
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