The Society for the Protection of Ancient Buildings (SPAB) is running practical, hands-on lime days around the country in June.
SPAB say their free advice line last year received 3,000 calls, a large proportion of them looking for contractors who could use lime mortar.
It is not surprising. Official figures show that 20% of houses are pre-World War One and would have been built using lime mortar. Many stone buildings also use lime mortars.
The SPAB courses (there are nine of them in various locations in Scotland, Wales and England) cost just Â£49 and are intended for those with prior knowledge of the trowel trades.
For details call: