A traditional Lakeland stone cottage in Grasmere was suffering from persistent damp penetration through its exposed west-facing gable wall. Our waterproofing team applied a breathable silicone-based masonry treatment that repels rainwater while allowing the stone walls to breathe naturally — essential for the health of traditional construction.
This traditional stone-built cottage in Grasmere faces the prevailing south-westerly weather, and its west gable wall bears the brunt of every passing front. The rough-hewn Lakeland stone and traditional lime mortar joints are naturally porous, and prolonged driving rain was saturating the wall to the point where damp was appearing on the interior plaster — ruining decoration, encouraging mould growth, and making the ground-floor living room cold and uncomfortable. Previous owners had applied a film-forming waterproof coating that had initially seemed to help, but over time this impermeable coating had trapped moisture within the wall thickness, actually making the damp worse by preventing the natural evaporation that stone walls rely upon. The trapped moisture was also causing the lime mortar to deteriorate, with joints crumbling and becoming even more permeable to wind-driven rain.
First, we carefully removed the existing impermeable coating using steam cleaning to avoid damaging the stonework. All deteriorated lime mortar joints were raked out and repointed with new NHL 3.5 lime mortar, restoring the wall's structural integrity and providing joints with the correct permeability for a traditional building. After allowing the repointing to cure for two weeks, we applied a breathable silicone-based masonry cream treatment. This penetrating treatment lines the pores of the stone and mortar with a hydrophobic silicone layer that repels liquid water (rain) while remaining open to water vapour (breathability). The treatment is invisible — the stone retains its natural colour and texture — and lasts 15-20 years before reapplication is needed.
The treated wall now actively beads and sheds rainwater rather than absorbing it. Water that previously soaked into the stone within minutes now runs off the surface. Internally, the damp patches dried out completely within six weeks of treatment, and the living room is noticeably warmer because dry stone has far better insulating properties than wet stone. The breathable nature of the treatment means the wall can still release any residual moisture vapour from within — critical for the longevity of both the stonework and the lime mortar. We provided a 15-year guarantee on the masonry waterproofing treatment.
The masonry waterproofing cream contains silane/siloxane active ingredients that penetrate into the pores of stone and mortar, lining them with a molecular-level hydrophobic layer. This causes water to bead on the surface rather than soaking in. Crucially, the treatment does not block the pores — water vapour can still pass through freely, maintaining the wall's natural breathability. The cream formulation ensures deep penetration (up to 15mm into the stone) rather than sitting on the surface where it would wear away quickly.
The repointing mortar was specified as NHL 3.5 lime — the correct binder for traditional Lakeland stone buildings. Unlike Portland cement, lime mortar remains flexible, breathable, and compatible with natural stone. It acts as a sacrificial element in the wall — the mortar weathers rather than the stone, and can be renewed periodically. The 1:2.5 lime-to-sand ratio provides durability while maintaining the softness needed for traditional stone construction.
The window-to-wall junctions were sealed with a neutral-cure silicone sealant that remains permanently flexible and adheres to both stone and timber. This sealant is vapour-permeable, maintaining the breathable performance of the wall treatment while preventing direct water ingress at these critical junctions.
Protect your stone walls from driving rain with our breathable masonry waterproofing service. We serve Grasmere and all Lake District villages with treatments suitable for traditional and listed properties. Contact us for a free damp assessment.
Choose which cookies you are happy for us to use. You can change your mind at any time from the Cookie settings button.
Needed for the website to work and to keep it secure, for example remembering your cookie choices, keeping a basket or booking together and protecting forms from spam. These are always on.
Remember choices you make, such as how a list is displayed, so the site works the way you prefer.
Help us understand how visitors use the website so we can improve it.
Used by third-party services such as maps, videos and social media, which may track you across other websites.