HDF Internal Doors
Materials of interior doors construction : HDF Internal Doors
Quote from Article entitled Materials of interior doors construction:
Shapes, used in the construction of aluminum doors, can be of two types - warm and cold. A warm aluminum shape in its structure has several sections or chambers, each of which is constructed using a press. Reducing of heat loss is achieved by filling sections of a shape with special polymeric materials which serve as thermal bridge. The construction of a cold shape is simpler; it consists of a single chamber without filling. It is recommended to set up such doors in places where there is no need for heat insulation.
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