Chimney Repair in Grange-over-Sands

The Problem

This double-fronted Edwardian villa occupies one of the most exposed positions in Grange-over-Sands, standing directly on the promenade with unobstructed views across Morecambe Bay. While the views are spectacular, the chimney stacks bear the full force of salt-laden south-westerly gales blowing across the bay. The main chimney stack — a tall, slender brick structure with decorative corbelling — had developed a visible lean of approximately 40mm at pot level. Closer inspection revealed that the mortar joints on the windward face had eroded to depths exceeding 50mm, with some joints completely hollow. The original lime mortar had been replaced at some point with a hard cement mortar, which had cracked rather than flexed with thermal movement, allowing salt spray to penetrate deep into the brickwork. Several bricks in the corbelled detail had spalled severely, with their faces completely detached. The lead flashings were original — well over a century old — and had thinned to the point where they were perforated in multiple places. The flaunching had cracked into several pieces, and one of the three pots was visibly tilting. A structural engineer consulted by the homeowner had recommended either demolition and rebuild, or stabilisation with reinforcement — the owners opted for the latter to preserve the original Victorian decorative brickwork.

Our Solution

After erecting a full chimney scaffold, we began by carefully removing the pots and flaunching to expose the stack top. Three stainless steel helical reinforcement bars were installed vertically through cored holes in the stack, resin-bonded into the solid brickwork below roofline to anchor the stack securely. The lean was not corrected — attempting to push the stack back would risk cracking the decorative corbelling — but the reinforcement ensures it cannot move further. Every joint on all four faces was then raked out to a minimum depth of 30mm and repointed with NHL 3.5 natural hydraulic lime mortar, restoring the breathability that the previous cement pointing had destroyed. The six severely spalled bricks in the corbelling were carefully cut out and replaced with matching reclaimed Edwardian bricks sourced from a demolition in Lancaster. All lead flashings were stripped and renewed in Code 5 lead — we specified Code 5 rather than Code 4 due to the extreme coastal exposure this Grange property faces. New pots were fitted with generous lime flaunching, and stainless steel cowls were installed to reduce rainwater entry into the flues.

The Result

The stabilised and restored chimney stack now presents the same elegant Edwardian profile it has always had, but with significantly enhanced structural security and weather resistance. The stainless steel reinforcement provides permanent stability against wind loading, while the breathable lime mortar allows the salt-contaminated brickwork to dry out gradually — a process that will continue over several years as trapped salts migrate to the surface and are washed away by rain. The Code 5 lead flashings provide the heaviest practical protection for this demanding coastal position, and the cowled pots have eliminated the rain entry that was causing flue condensation and chimney breast damp in the rooms below. The homeowner was delighted to preserve the original decorative brickwork that is such a feature of Grange-over-Sands' promenade architecture, and the chimney repair has secured this landmark feature for generations to come.

Stainless Steel Helical Reinforcement

The helical bars used to stabilise this chimney are manufactured from austenitic stainless steel, providing complete immunity to the salt-laden environment that accelerates corrosion of standard steel fixings. Each bar was installed into a diamond-cored hole slightly larger than the bar diameter, then bonded with a two-part resin grout that fills the annular gap and provides a permanent structural connection. This technique is widely used in heritage masonry conservation and avoids the need to dismantle and rebuild decorative features.

NHL 3.5 Natural Hydraulic Lime Mortar

Natural hydraulic lime mortar is essential for repointing this salt-contaminated brickwork. Unlike cement mortar, which is harder than the bricks it joins, NHL 3.5 lime mortar is designed to be the sacrificial element — it will erode before the bricks, and can be renewed without damaging the historic masonry. Crucially, its high vapour permeability allows salt-laden moisture trapped within the brickwork to escape through the mortar joints rather than crystallising behind the brick faces and causing the spalling damage seen on this Grange-over-Sands stack.

Code 5 Milled Lead Sheet

We specified Code 5 lead (2.24mm thick) rather than the more commonly used Code 4 (1.8mm) specifically because of the extreme coastal exposure. Salt spray accelerates lead corrosion, and the additional thickness provides a proportionate increase in service life — estimated at 120+ years in this position compared to perhaps 80 years for Code 4. The cost difference is modest relative to the scaffold and labour costs, making the upgrade excellent value for long-term protection.

Breathable Silane Water Repellent

The silane-based treatment applied to the western face is a molecular-level water repellent that lines the pores of the brickwork without blocking them. Water droplets are repelled from the surface, dramatically reducing the amount of salt spray absorbed into the masonry, while water vapour can still pass through freely. This sacrificial treatment will gradually wear off over 8-10 years, at which point it can be reapplied as part of routine chimney maintenance.