Tullibole Castle is a Category A Listed Tower House dating from the early 17th century. There is a heraldic marriage stone above the front door inscribed with the date 2 April 1608. The architectural development of the building illustrates the transition from Scot’s Tower House to Laird’s house in the 18th century. The castle was previously restored in 1957/9 by Lord Moncreiff.
Scope of Work
Pictured: Tullbole Castle: before works.
LTM were contracted by the owners to undertake the conservation and repair of the historic fabric. Works included: careful removal of existing cement harling and reinstatement of traditional lime harling with limewash finish; new slating to match existing; renewal of leadwork and cast iron rain water goods. A maintenance manual and guide was also prepared for the client.
[ View the full Case Study Slide Show ]
Challenges and Considerations
Pictured: Harling delamination from masonry background and between coats.
The original brief detailed selective patch repair and cleaning of existing cement harling. However, upon investigation it was discovered that the cement harling had been applied over an untreated earlier cement harling. This caused concern regarding the condition of the harling material, the compatibility of new mortars, and therefore the longevity of the proposed repairs.
In consultation with the client, LTM subsequently proposed the full replacement of the existing cement harling with a more appropriate (technically, aesthetically and historically) lime based harling. With careful consideration of the specifications for the reinstatement work, LTM were able to propose an alternative package of works which came within the same budget as the original proposal.
[ View the full Case Study Slide Show ]
Solutions to Problems
Pictured: Hand cast application of harling.
The existing cement-based harling (dating from the late 1950’s) was causing considerable deterioration of sandstone masonry substrate. LTM’s masons repaired the background using compatible stone pinnings and lime mortar in advance of the new lime harling. The final coat of harling was finished with 6 coats of limewash.
The careful removal of the cement harling revealed underlying remnants of original materials and finishes, informing and directing the conservation works. LTM’s masons uncovered two specific areas of original lime harling and limewash, which dictated the new lime harling in terms of specification (through mortar analysis) and application (which was hand cast).
[ View the full Case Study Slide Show ]