Chimney Lining Romford — HETAS Registered

Chimney Lining — Why It Matters

An unlined or deteriorated flue allows flue gases — including carbon monoxide — to pass through the brickwork and into the fabric of the building. It also allows moisture and condensates from combustion to penetrate the masonry, causing damp that appears well away from the chimney and is frequently misdiagnosed for months. One of the most common causes we find is damage during loft extension works — the liner is cracked or dislodged and the homeowner has no idea until performance drops. We have carried out liner replacements on properties where the living room was already fully decorated: on those jobs the opening comes from the external wall, all builder's work is done outside, and the brickwork and render are reinstated before we leave. The finished aperture is not visible to anyone who was not watching.

The liner diameter is determined by the appliance and fuel type. A 125mm multifuel flexible liner is standard for most solid fuel stove connections — the flex adaptor at the builder's opening bridges the liner to the stove pipe above the constructional hearth. For open fires the specification changes: 180mm minimum for gas open fires and GFE appliances, 200mm for solid fuel. The extra 25mm on the solid fuel diameter is a safety margin for soot build-up — if a chimney is not swept regularly, draw is not badly affected and smoke spillage is prevented. Both sizes are installed to a stainless steel gather hood which sits within the existing brick gather, sealed and backfilled to eliminate leakage into the cavity surrounding the flue. We inspect and clean the gather before the liner goes in — the condition of the gather at installation determines the long-term performance of the lining.

We install 316-grade Class 1 twin wall flexible liner as standard for solid fuel work. Class 2 gas flex — formerly sold as COPEX in the 1970s and 80s and still known by that name by many customers — is a thinner compound liner and not the correct specification for solid fuel appliances. Class 2 with solid fuel fails quickly. We also carry out full chimney reinstatements where the original chimney breast has been removed: new flue system installed internally through the floors to roof termination, brick fireplace built around on completion. It is the most complex job in this category and one that many contractors will not take on. HETAS certification is issued on every completed installation, building control notified on your behalf.