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<\/p>\nA project to dry out Charles Rennie Mackintosh\u2019s masterpiece the Hill House has reached a \u201ccritical juncture\u201d, with conservators having to painstakingly remove the cement render that was a major factor in extensive water damage.<\/p>\n
A giant steel box around the property in Helensburgh, Argyll and Bute, was completed in 2019 to protect the building\u2019s saturated walls from further damage from the elements and to allow it to gradually dry out as part a long-term conservation programme.<\/p>\n
The Hill House has been badly affected by the driving rain on Scotland\u2019s west coast since its construction in 1904.<\/p>\n
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Materials and techniques that were at the cutting edge of architectural design in 1900 have not withstood a century of the west of Scotland\u2019s wet weather<\/p>\n
ANDREW MILLIGAN\/PA<\/p>\n
A Portland cement render, or \u201cskin\u201d, was applied to the building in 1902-04 under Mackintosh\u2019s instruction, when it was thought to be a wonder product that would protect against the elements.<\/p>\n
However, the render did not live up to expectations. Water penetration over the decades damaged both the structure of the house and the bespoke interior decoration.<\/p>\n
After several years of being sheltered by the steel box, the walls of the Hill House <\/a>have dried out enough for the render to be painstakingly chipped off. The removal of the render is now well under way.<\/p>\n The house was commissioned by Walter Blackie, a Glasgow book publisher, and the interior design was a collaboration between Mackintosh <\/a>and his wife, Margaret Macdonald.<\/p>\n Caroline Clark, director for Scotland at the National Lottery Heritage Fund and Phil Long, chief executive of the National Trust for Scotland<\/p>\n ALAN MCATEER\/NATIONAL TRUST FOR SCOTLAND\/PA<\/p>\n Phil Long, chief executive of the National Trust for Scotland (NTS), which cares for the property, said: \u201cIt\u2019s difficult to overstate the international importance of Mackintosh and Macdonald and of the Hill House, and so delivering this project is of vital importance in preserving Scotland\u2019s \u2014 and the world\u2019s \u2014 design heritage.<\/p>\n \u201cFrom the moment they were realised, Mackintosh\u2019s designs<\/a> had a profound effect on the development of early 20th-century international architecture and design, and more than a century later, they remain startling.<\/p>\n \u201cThe Hill House is one of the architect\u2019s greatest remaining masterpieces, and in its breathtaking interiors, realised in collaboration with his wife, the artist and designer Margaret Macdonald, their combined vision reached its peak.<\/p>\n \u201cThis is why restoring this building is of such vital importance to Scotland\u2019s and the world\u2019s creative heritage.\u201d <\/p>\n \u2022 Has Glasgow squandered legacy of Charles Rennie Mackintosh?<\/a><\/p>\n Long continued: \u201cThanks to the National Lottery Heritage Fund\u2019s generous support, the project has reached a critical juncture. The removal of the render allows us to explore the detailed construction of the building and gain further insight into Mackintosh\u2019s architectural innovation, as well as the constraints he was overcoming.<\/p>\n A stonemason at work removing the Portland cement render from the walls<\/p>\n ALAN MCATEER\/NATIONAL TRUST FOR SCOTLAND\/PA<\/p>\n \u201cThe protective box has controlled the drying out of the building, which, if done too fast, may have caused further damage.<\/p>\n \u201cAfter expert analysis, it was clear that full replacement of the often-patched Portland cement render was the only tenable option for enabling the restoration work that ensures the building\u2019s long-term survival.\u201d<\/p>\n NTS said it would continue to work with internationally-recognised specialists to finalise a replacement surface render that would maintain the integrity of Mackintosh\u2019s vision, but would be able to \u201cbreathe\u201d.<\/p>\n![\"Caroline](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2026\/02\/\/b44388a0-50f1-47c0-95fd-73bd1e965ab8.jpg\")
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