A Local Stone Cottage Renovation Using Lime

We’re always pleased to see traditional buildings being restored using the right materials, and this recent local stone cottage renovation is a fantastic example of how lime can transform and protect older properties.

These images were kindly supplied by Jud Thomas of Just In Lime, a local lime specialist with extensive experience in the careful restoration of traditional buildings.

Before - When the stone cottage was covered in cement render. 

The project began with the removal of the existing cement render. While cement-based renders are often used in modern construction, they can create significant problems when applied to older solid-wall properties. Unlike traditional lime finishes, cement is dense and impermeable, trapping moisture within the wall structure rather than allowing it to evaporate naturally.

Over time, this trapped moisture can lead to a range of issues, including:

• Damp internal walls
• Mould growth
• Damage to the underlying masonry
• Reduced thermal performance
• Accelerated deterioration of the building fabric

Old cement render removed and repair work carried out. 

By carefully removing the cement render, Jud was able to allow the cottage walls to breathe once again, restoring the building’s natural ability to regulate moisture effectively.

Once the masonry was exposed and allowed to stabilise, minor repairs were carried out where needed before a smooth finish coat of Natural Hydraulic Lime (NHL) plaster was applied. This breathable lime plaster provides long-term protection while remaining sympathetic to the movement and character of traditional stone construction.

To complete the restoration, the cottage was finished with a traditional limewash, created using NHL lime and blended with yellow ochre pigment to achieve a warm, fresh appearance that complements the property’s historic character beautifully.

Lime Repair work on old stone cottage in Pembrokeshire

How to Mix Saint-Astier St. Astier NHL 2 Limewash

Creating a breathable, traditional limewash with St. Astier NHL 2 is simple when mixed correctly.

• Mixing Ratio - Use 1 part St. Astier NHL 2 to 1–2 parts clean water, depending on your preferred opacity and finish.
• Mix Thoroughly - Whisk the lime into the water until it reaches a smooth single-cream consistency. Allow the mixture to slake for around 10 minutes, then strain to remove any lumps before use.
• Application - Lightly dampen the masonry surface and apply using a specialist block brush in thin, even coats for the best results.
• Curing - Protect freshly applied limewash from rapid drying caused by direct sunlight or strong winds. Lightly mist with water as needed to support proper carbonation and curing.

Top Tip: Saint-Astier St. Astier NHL 2 is ideal for traditional limewash, with its soft, breathable formula allowing moisture to escape naturally and helping prevent flaking on older, delicate masonry. However, for maximum breathability and the most historically authentic finish, mature lime putty is often the preferred choice for traditional limewash applications.

Yellow Ochre Limewash applied to a traditional stone cottage.

We hope this article has inspired you to start your own project or given you the confidence to explore working with lime. If you’re planning a new job, getting the right advice from the start can make all the difference. Our in-house lime specialists, Ian and Dan, are always happy to help with guidance and product advice. You can also speak with experienced professionals such as Jud Thomas, the local lime specialist behind this project. With many years of hands-on experience restoring traditional buildings, Jud is a trusted expert and a familiar face here at Celtic Sustainables.

Jud is based in Pembrokeshire and Ceredigion. https://www.facebook.com/profile.php?id=100057488228065

A useful source of information is the book "Lime in Building - A Practical Guide by Jane Schofield"

What a transformation!