What is Fireshield Breather Membrane?
Fireshield Breather Membrane is a vapour permeable membrane for use on walls behind cladding. The unique coating eliminates fire spread rather than just resisting it. It is installed and ﬁxed to the substrate in the same manner as standard breather membranes using mechanical ﬁxings.
Fireshield (right) and a competing fire retardant membrane (left) are fixed to a 10mm OSB panel with staples. A butane torch is positioned approx. 10cm from the face of the membranes at a 45 degree angle. Two cameras capture the view from front and back.
After 1 second
Immediately after the butane torch fires, the competing membrane begins to melt and shrink away from the heat source, exposing the OSB. There is no physical change to Fireshield.
After 1 minute
On the left side, the competing membrane retreats further from the flame and the OSB begins to burn. On the right side, the flame has caused Fireshield’s intumescent surface to react and ‘puff up’ which protects the membrane and the OSB.
After 6 minutes, 30 seconds
The reverse-side of the OSB on the left begins to discolour and smoke as the flame penetrates the OSB under the competing membrane. Fireshield’s fire-proof surface continues to intumesce in response to the fire. No discolouration or smoke on the reverse-side of the OSB on the right is observed.
After 11 minutes, 35 seconds
The OSB panel under the competing membrane on the left is breached by fire, and flames appear on the reverseside. Fireshield continues to puff-up. No discolouration or smoke on the reverse-side of the OSB on the right is observed.
After 20 minutes
The competing membrane exposed the OSB directly to fire from the outset and, as a result, the OSB burned completely through before the test was over. The torch over Fireshield was left on for a full 20 minutes. Even though the membrane itself did not catch fire during that time, the front-side of the OSB panel only received minor scorch marks and did not ignite.