An introduction to Lime - Understanding the advantages & disadvantages of this alternative method
An introduction to Lime - Understanding the advantages & disadvantages of this alternative method
The Joint Position Statement 'Investigation of moisture and its effects on traditional buildings - Principles and Competencies’ launched last week at the PCA property Care Conference. One of the changes since the publication of the first draft is it now encourages providing ‘alternative options’ with both advantages and disadvantages. One of these ‘alternative’ methods may be the use of traditional strategies for repair.
Whilst the PCA have run a traditional methods of repair course in collaboration with SPAB (Society for the Protection of Ancient Buildings) members of the PCA technical team took the opportunity to delve a little deeper into one particular aspect of the course - Lime renders and mortars - to help better understand the advantages and disadvantages of this alternative method.
So what did PCA's Technical Manager James Berry think of it? What did he learn and what will he take away from the two-day course? Scroll down to read more...
The course - An introduction to Lime
The course took place at The Heritage Skills Centre located at the Home Farm buildings in the village of Coleshill, just outside Swindon. The building itself is a former farm dating around 1854 and something of a 'surveyors dream', making it an ideal setting for this type of course.
The first day was an introduction to lime. It was very much a foundation course and included a combination of presentations, starting with a look at the lime cycle, demonstrations and an opportunity to get involved and prepare and apply a number of the products. There was also a good variety of presenters including Marianne Suhr, Michal Wolf and Rob Workman.
If you are already relatively familiar with using traditional lime products then this day may have limited merit to you, but it covered a broad spectrum of limey topics including:
- hydrated limes
- hot and cold mixes
- limewashes
- sands
- hydraulic limes
The Lime Cycle
The second day was focused on getting into the details of hot limes, which is now considered to be the most common use of lime products historically. This was a much more technically detailed day, very much aimed at those with a more solid understanding of lime products.
The hot limes in building was led by Nigel Copsey who seems to defy convention as far as the ‘Lime revival’ goes, applying lime in extremely cold conditions and without waiting for weeks between coats! But he was highly knowledgeable and seems to come at things from an extremely practical point of view. In fact there was a stark contrast between the two days, with Nigel very much contradicting the advice given just 24 hours earlier! However, like the first day this was a good balance and mix of presentation, demonstrations and getting stuck in yourself.
Overall the course was both interesting and engaging. I left after the two days feeling I had gained a lot of knowledge, but also inspired to go off and do further research. I will definitely be ordering a copy of Nigel’s 2019 book 'Hot Mixed Lime and Traditional Mortars: A Practical Guide to Their Use in Conservation and Repair'...so look out for a review coming soon!
It was also a great opportunity to learn about alternative options, even if it was just to establish that there are alternative alternatives...