GB
29
When recessing the insert, adjacent walls that are not classed as fire walls or are considered unsuitable for heat loads must be protected
by non-combustible material according to the specification below.
All joints on the non-combustible material must be sealed using the manufacture’s recommended method. The area between the insert
and the recess must be ventilated according to the specification/dimension diagrams on page 31.
When top connecting a steel flue please refer to the relevant manufacturer’s installation instructions. Observe the safety distances
to combustible material that steel flues require. Heat radiation from the hatch is strong and is why combustible material must not be
placed closer than 1.5 m in front of the hatch. When recessing, building material must not be in direct contact with the insert due to the
thermal expansion of the insert.
Material requirements
The building material must not be combustible.
The thermal conductivity coefficient may be a maximum of 0.14 W/mK.
The thickness of the building material must always be at least 100 mm.
In cases where the building material’s insulation properties are given as a U-Value, this must be a maximum of 1.4 W/ m²K.
List of suitable materials:
Aerated concrete: =0.12-0.14
Vermiculite:
=0.12-0.14
Calcium silicate: =0,09
Sealing
If the recess is to extend to the ceiling, a seal must be made above the convection exhaust. This is to prevent hot air collecting in the
recess closest to the ceiling. The seal must a maximum of 100 mm above the convection exhaust’s upper edge and must be made up of 20
mm thick building boards made of calcium silicate or a panel with at least a 50 mm thickness of rock wool on top.
Convection air
The convection air ventilates the surround, cools the insert and transports the hot air out into the room. The total sum of the effective
cross section area up and down must not be less than the stated values. The air intake must be positioned somewhere between the floor
and the bottom of the insert, up to or on the sides of the recess. The vent must be positioned above the insert’s highest point up to or to
the sides of the recess.
If the air intakes and exhausts are to be located on the sides, the areas on the left and right hand sides must be of equal size to ensure
that the insert is evenly cooled.
Observe the minimum distance up to the ceiling (see diagram on page 31).
Convection air in: 600 cm²
Convection air out: 600 cm²
If the convection outlets are directed upwards the following applies
- the recess must be free-standing or placed against non-combustible walls
- the distance from the air outlet to combustible roof must be at least 700 mm
To service the hatch’s runners, all recess parts built out in front of the moulding below the hatch, e.g. shelves, must be removable.
Note that building regulations apply regarding the area below and in front of the insert, see section ”Hearth plate”.
Recessing the insert
RECESSING ThE INSERT