Fire rated wooden doors are generally made by enclosing a thick layer (core) of some fire resistance material (gypsum, glass, fire retardant fibre etc) sandwiched between two sheets of wood or ply.
These are generally used at the openings to escape route in case of fire, like - between kitchen to escape route, office room to corridor, important storage room to corridor etc.
In case of fire these doors can withstand it for some time depending on their thickness and temperature rating.
The wooden fire doors are available in various ratings depending on their ability to withstand the fire. Generally the ratings vary from 30 minutes to 2 hours at a temperature up to 200 degree centigrade.
In case still higher rating is required one has to go for steel, metal or glass doors which can withstand for a longer time.
The cost of wooden fire doors varies depending on the specifications but as a rough guideline the prices for a standard size door are in the range of 5000 - 8000 per piece.
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