that a cardboard cylinder is formed around the flue unit and inserted in the hole whilst
making good. Remove the cardboard cylinder after making good.
7.9 Combustible walls (wood, fibreboard, plasterboard etc.).
1.
Building regulations require that the outer surface of the flue tube and terminal must
not be closer than 25mm to combustible material and must be lined with steel sleeve not
less than 0.5mm thick (See figure 13). The sleeve can be made by coiling a piece of
sheet steel to between 125mm & 127mm outside dia. and fitting it to the combustible
parts of the construction.
2.
Mark out and cut a hole
177mm diameter through the
plasterboard.
3.
Cut a hole of about 165mm
in the vapour barrier. Clear the
insulation quilt from the hole
area and cut a 177mm dia.
hole in the timber sheathing
and breather paper.
4.
Drill a 127mm diameter
hole through a non-
combustible (brick etc.) outer
wall.
5.
Fit the steel sleeve. The
sleeve should not protrude
more than 10mm into the
cavity. The sleeve should be
sealed to the inner leaf of the
wall at both ends with a non-
setting thermal mastic sealant.
6.
If the outer wall is combustible drill a 177mm hole and fit the liner sleeve through to
this wall.
7.
Cover the hole with a steel plate size 500mm (Vertical) x 235mm, not less than
1.5mm thick with a 127mm diameter hole in the middle. Fix with suitable screws and
plugs.
8.
Where the whole wall is of combustible material a non-corrosive plate 455mm square
with a 127mm diameter hole in the centre must be fitted to the outer face of the wall.
9.
The area immediately behind the firebox must be separated from the combustible
elements of the inner wall by 25mm thickness of non combustible material.
This can consist of the usual 13mm plasterboard wall lining plus 12mm of “Superlux”
or similar non-combustible material (See figure 13).
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INSTALLER GUIDE
Figure 13.
