DM 36 is designed for smaller output inserts, stoves and cookers.

DM 44 is designed for inserts, stoves and small open fires.

Available in 2 internal diameters, 180mm and 200mm. All inner blocks fit into the same external block.

DM 54 for larger open fires and appliances.

Available in internal diameters Ø300mm and Ø345mm. Both inner liners fit into the same external block size.

• Bed the base plate of the firechest onto a suitable foundation/constructional hearth in accordance with Building Regulations and at the level required on site using Isokern Lip Glue.
• Install the firechest using lip glue making sure all elements are level. 100mm of brick/blockwork must be built around the sides and back of the firechest to comply with Building Regulations. The inside of the firechest must be finished with a suitable fireback or firebrick slips.
• Install the gather using lip glue making sure all the elements are level. The front face of the gather can be finished with platerboard, rendered or clad in masonry. Lintels may be required above the gather to help carry the brick or blockwork. The maximum loading capacity of the ISOKERN firechest and gather is 2500kg.

• Pre-stressed lintels or a suitable cast-in-situ concrete slab must be provided above the stove recess,please make sure they are strong enough to carry the load(see appropriate Isokern DM drawing for aperture size). It is recommended to have a minimum of 600mm of stove flue pipe before connecting to the support block.
• The support block is bedded onto the lintels using a weak mix mortar. A stainless steel adaptor is used to create a positive connection from the support blcok to the stove flue pipe(fibre rope should be used to create a seal).

• A soot door casing and access flue block must be used below the flue pipe entry.
• The DM 45° access kit is then used for the connecting flue pipe
• A suitable wall sleeve must be used to seal the cavity wall.
• Any combustible insulation within the wall must then be kept away from the single wall connecting flue pipe by at least 1.5 X its diameter.
• Fibre rope is used to seal between the flue pipe and wall sleeve , a suitable trim collar can be used to finish the inner wall surface.

• Code 4 lead flashing to be fitted at roof level as per Building Regulations. We recommend that you scorch a 5-10 mm deep channel into the outer surface of the casings and fold in the top edge of the flashing .
• Finish the outer surface of the casings above the roof with 2 part waterproof render.
• The recommended mix is 1:2:5-6 cement:lime:sand for the undercoats.1:2:8-9 cement:lime:sand for the final coat.
• The number of coats required will depend upon the degree of exposure, generally a two coat mix is acceptable.
• The mix may very due to climate conditions ,the thickness of any one coat should not exceed 15 mm and each subsequent coat should be reduced by approximately 3 mm
• Isokern concrete capping for render to be lip glued onto the last casing .

• To take brick or stonework externally a corbel is fitted just below the roof.
• Use trusses and trimmers to brace the cladding as it passes through the roof
• Code 4 lead tray with 50 mm upstands and stepped flashing to be fitted in accordance with Building Regulations .
• A 50 mm upstand should be fitted tight to the outside of the flue block  and where possible turned in by approx 10 mm.
• Lead trays should be coated with bituminous paint where it is in contact with mortar.
• The D.P.C tray should be fitted at least 150 mm above the lowest point of intersection with the roof.
• Weep holes should be provided at the front of the stack above the tray for water drainage .
• Casings can be deleted above the corbel if stack height is less than 1.4 m above the roof.

Option 1 – Raincap Ventilated Option (installation with 0 distance to combustibles for straight rendered chimneys only)

• Take the last flue block up through the capping ,do not fill the gap between the flue block and capping.
• Push fit the aluminium top ring onto the flue block and make sure there is a 10 mm air gap between the outer edge of the ring and the capping .
• The flue block may need cutting to suit.

Option 2 : Chimney Pot Option

• This option always required a 38mm distance to combustibles from the outside of the block .
• Fit a chimney pot at least 75mm down into the capping and flaunch with 1:3 cement and sharp sand to seal around .
• This option is not possible if 0 distance to combustibles is required.

• After installation is complete, tests and checks should be carried out in accordance with document J of the Building Regulations
• A chimney notice plate must be completed and permanently fixed in the dwelling ,ideally near the electrical consumer unit.
• The checklist and notice plate are available from Schiedel Isokern.

• The chimney should be left for at least 72 hours before use , then start only with small fires for the first week and gently increase thereafter.
• The chimney should be swept at least twice a year ,once before the heating season and once after the heating season .
• You may need to sweep during the heating season depending upon use.
• The brush should be a medium density polypropylene bristle type and should be the same diameter as the flue. Steel brushes must not be used to sweep the Isokern pumice flues
• Always follow the appliance manufacturer’s operating instructions.
• Always burn approved fuels or dry seasoned wood .
• Avoid burning unseasoned wood and slow burning of solid fuels as this can product excessive soot and condensation which in turn cause soot fires and damage.
• If correctly installed, operated and maintained these systems should last the life of the dwelling.