Last December (2021) we moved to a stone-built detached house dating to c.1800 which has no apparent serious damp problems for a property of that age.
A short while ago, after being here for about 10 months, we noticed a few live mould spots on an 18th century watercolour. At about the same time, similar mould spots appeared on a longcase clock and a few pieces of furniture.
We bought a few humidity gauges and were surprised to find the relative humidity throughout the house was mostly between 70% and 78%.
The use of dehumidifiers in two rooms brings the level down to between 50% and 65% but they need to be on permanently to maintain that level.
Do collectors and dealers with a similar problem use dehumidifiers so extensively or is there another way to solve the issue without moving house?!
If the use of dehumidifiers is the only answer, can anybody recommend through personal experience which are the most successful in terms of results and economy?
Any advice would be hugely appreciated.
John Theophilus
