Timber Frame Building. Firebox In Front Of Wall; Wall Preparation For Flue Tube; Core Drilling; Hammer And Chisel Cutting - Baxi GALLERY Series Installer's Manual

INSTALLER GUIDE

7.5 Timber frame building. Firebox in front of wall.

This installation is for use in timber framed buildings in conjunction with a fire
surround having a minimum depth of 153mm (6 inch).
1. The non-combustible hearth must project at least 300mm in front of the convection
box flanges and be at least 625mm wide. For this type of installation the hearth must be
at least 50mm thick over its total area (Figure 1). Installation must be in accordance
with the current edition of Institute of Gas Engineers publication IGE/UP/7.
2. The back surface of the firebox and flue tube assembly must be separated from the
timber frame by 25mm of non-combustible material. This can consist of the usual
13mm plasterboard wall lining plus 12mm of "Superlux" or similar non-combustible
material. The opening should be between studs.

7.6 Wall preparation for flue tube.

1. The flue must be installed so that it is at right angles to the back panel of the fire all
round the flue circumference. The fire itself should be fitted vertically against a flat
wall. Where this is difficult to achieve due to building inaccuracies care should be
taken to ensure that the back of the fire is not stressed in any way due to distortion of
the assembly when tightening the fixing screws. Where necessary, non-combustible
packing pieces should be used to provide a satisfactory fixing surface.
2. Before cutting the hole in the wall make sure that the height to the top surface of the
finished floor is known. The height from this surface to the flue hole centre is shown in
figure 14.
3. If a loose hearth or plinth is to be used, the height from its top surface must be used
when determining the flue height.
4. Place dust sheets on the floor and over any furnishings etc.
5. Make sure that the centre of the flue hole is as shown in figure 14.
6. Cut the hole for the flue unit.

7.7 Core drilling.

1. Drill a pilot hole through the wall. Inspect the hole to ensure that it is in the
brickwork and not in mortar. If it is in mortar, it is advisable to reposition the hole
approximately 25mm away (Ensuring that all other clearances to firebox are complied
with). Remember to reposition the screw fixing holes.
2. Drill the flue hole with a 5in. (127mm) core drill.
3. Remove any combustible wall cladding material from the area behind the firebox as
described previously.

7.8 Hammer and chisel cutting.

1. Mark a 127mm (5in) diameter circle for the flue hole. Chisel out the area marked.
It may be necessary to make good both the internal and external wall faces. To achieve
a neat finish and to make any future removal of the flue unit easier, it is recommended
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