A 190-year-old leak at Kingston Lacy house has finally been traced to a design flaw by Sir Charles Barry, the architect of the Houses of Parliament.

Persistent Leak Finally Explained

For nearly two centuries, Kingston Lacy house, a magnificent country mansion, has been troubled by a persistent and perplexing leak. Despite countless investigations and reports from numerous experts, the source of the moisture intrusion remained elusive, causing ongoing damage and requiring consistent maintenance.

The Architect's Mistake

The National Trust team responsible for the preservation of this Grade I-listed property has uncovered the root cause: a fundamental design flaw introduced by Sir Charles Barry. Barry, renowned for his work on the Houses of Parliament, designed a new cupola for the 17th-century house in 1835.

Glazing Error

His design incorporated a seemingly aesthetic choice that proved detrimental. He specified that the windows of the dome-shaped cupola be glazed ‘inside out’. The National Trust believes this was to enhance the visual appeal of the cupola for visitors.

By positioning the protective putty on the interior side of the glass, Barry inadvertently created a pathway for moisture to penetrate the window frames. This allowed water to seep into the timber, leading to rot and deterioration.

Years of Repair Attempts

Historical records show the Bankes family, previous owners of Kingston Lacy, undertook repair work on the cupola. Since the National Trust assumed stewardship in 1981, they have also implemented several repair campaigns, addressing the symptoms without resolving the underlying issue.

Current Restoration Efforts

The team’s investigations, combining detailed surveys, monitoring, and historical research, pinpointed the exact source of the problem. The current repair project will be executed in phases over the next year.

Comprehensive Repairs

The team will carefully re-glaze the cupola windows, ensuring the putty is applied correctly on the exterior. They will also investigate and repair defects in the leadwork surrounding the base of the cupola, which has also contributed to water ingress.

A National Trust spokesperson emphasized that the detailed work provides a clear understanding of the leak’s causes, enabling a permanent solution. The aim is to halt the cycle of deterioration and safeguard Kingston Lacy for future generations.