White wood 1 Red Miranti forms the skeleton of the fire door. Calcium
Silicate boards which acts as the core of the fire resistance door is
then attached to the white wood using an adhesive and then nailed.
Gypsum board is then
attached to the other side of the door using an
adhesive and onto this gypsum board we spread the adhesive and small
wooden blocks are placed uniformly. A second layer of gypsum is then
attached on top of the wooden blocks using
an adhesive. E.g.: Fevicol.On to this second layer of gypsum, a calcium silicate board is glued
using fevicol. Now we have an unfinished door with Calcium Silicate
boards of the 2 opposite sides.
This unfinished door is then placed in the pressing machine and then
heat pressed for a minimum time period of 90 min. On completion of the
pressing procedure, white wood/red miranti is glued and nailed on to
both sides of the fire door. The gaps on the 4 edges of the fire door is
then tightly sealed using a fire resistant sealant. This is the
process in which a fire resistant door is heat pressed.