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 14). 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 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 14).
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INSTALLER GUIDE
Figure 14.
