Eldfast chimney lining comparison with flue lining

ELDFAST is a totally ceramic material composed of two elements

  1. A refractory ceramic aggregate i powder form
  2. A resin bonding agent


These together create a “slurry” with adhesive properties when applied under pressure.

Traditionally, only materials containing water, lime/clay mortar or cement have been available to re-parge a flue internally, these materials are now know to be prone to acid attack and deterioration.



Eldfast is an in-situ applied lining, drawn through the flue by means of a “plug”, leaving a 4mm nominal thickness of material on the flue face.

Eldfast will follow the contours of the flue (although some rounding of corners is likely), rather than drastically reduce the free area, this is of particular benefit when wishing to retain future usefulness of the fireplace for open fires (requiring a minimum 8 inch/200 mm cross sectional area) or when dealing with smaller flue areas initially.

The photo above illustrates a standard chimney without Eldfast treatment, it is susceptible to carbon monoxide leakage as the video below shows, and build up of soot. The chimney on the right shows a chimney that has been treated with Eldfast. It has blocked all the cracks and internal damage of the chimney to prevent the dangerous fumes leaking in to your home and potentially causing sickness or even death.

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