It is important to support the chimney pot before removing the flaunching. Flaunching is the
mortar base holding the chimney pot in position on top of the chimney stack. Even though the
pot will be discarded once removed, it can damage other areas of the roof if it is not taken
down carefully. Tie a length of rope around the top of the pot (A) and a second rope around
the chimney stack (B). Then secure by attaching a rope from A to B on both sides of the
stack. This should hold the pot in position before removing the flaunching.Use a cold
chisel and club hammer to remove the damaged mortar. Untie the ropes and remove the pot. The
new pot needs to be placed in a central position to fit the flue. If the base of the new
pot is square, it is designed to fit over the flue exactly. If the new pot does not fit
exactly or has a different shaped base, then the pot will need supporting before replacing
the mortar base.
Use strips of slate strategically placed around the base of the pot to
support it in the correct position. Brush away the unwanted material and dampen the surface
of the stack. This is necessary, especially in warmer weather, to stop the mortar from
losing moisture too quickly, which would result in cracking. Use mortar consisting of
approximately a 1 : 4, cement : sand mix to replace the flaunching around the base of the
new pot.
