Dry Rot in Action: Case Study from a Grade II Listed Property
Historic buildings can conceal unexpected surprises, and today’s survey uncovered one worth sharing — an active fungal outbreak visually consistent with dry rot (Serpula lacrymans). Although famously feared, few people ever see this organism operating in real time.
What We Found
Most people know the term “dry rot”, but few ever see it in action. The photos show white mycelium spreading across the floor, yellow “tears” where the fungus exudes moisture and enzymes, and — most strikingly — a rope-like rhizomorph stretching between two stacks of timber, effectively a fungal “feeding line” searching for its next food source.
Why Dry Rot Is So Effective
Dry rot has earned its reputation as a predatory organism. Once established, it can:
-
Transport moisture through its own structures to colonise drier areas
-
Break down timber fibres until they crumble into brittle cubes
-
Travel through masonry joints and across concrete floors in search of its next food source
-
Mycelial growth
-
Rhizomorph “feeding strand” moving between timber stacks.
-
Dry rot mycelium spreading across the basement floor.
Little wonder historic folklore once suggested it “grew out of bricks overnight” — and when you see a strand marching across a stone floor, you can understand why.
A Reminder About Building Care
In this instance, the outbreak was confined to loose timber, not the building fabric. However, it highlights:
-
The importance of good ventilation in basements
-
Why stored timber should not be left in damp environments
-
How proactive inspection prevents small issues becoming major ones
Decay may look slow, but fungi like this operate with surprising purpose when conditions allow.
Dry Rot and Historic Buildings
Dry rot does not mean disaster if caught early. Good building management — controlling moisture, improving airflow, and removing affected material — usually avoids invasive work and protects historic fabric.
Need Help with a Historic Property?
Our Chartered Surveyors and Estate Agents specialise in heritage buildings across Northamptonshire and surrounding counties.
Whether you are buying a period home; maintaining a Listed building; or preparing a property for sale or letting, we can provide the expert guidance and clear reporting for successful results.
