46 sash windows repaired Grade II listed at Harrogate School by Ventrolla

Key features: Commercial, Grade II Listed, Sash Windows, Education, Renovation, Ventrolla Perimeter Sealing System (VPSS), Edwardian

A Symphony of Restoration at St Aidan’s School

Students and staff at St. Aidan’s High School in Harrogate are reaping the benefits during a chilly start to the year after calling in Ventrolla to upgrade the sixth-form building’s ageing sash windows.

The restoration specialists renovated 46 of the Grade II Listed building’s sash windows, of which four were large Venetian sashes after their deteriorating condition rendered the windows draughty and inoperable.

New like-for-like timber was used to replace all rotten timber routed out of the original box frames and sills by Ventrolla, so the features of the window were preserved. The sash cords were then replaced, pulleys serviced, and sashes correctly balanced to ensure the smooth and safe operation of the windows.

St. Aidans School in Harrogate, a Grade II listed institution with a storied history, sought to breathe new life into its architectural heritage. Ventrolla was commissioned to undertake the meticulous restoration of forty-six distinctive sash windows, marrying the preservation of historical elegance with modern functionality.

The Heritage Dilemma

Rotted Timber and Fading Grandeur

The sash windows at St. Aidan’s School, weathered by time, bore the scars of decay. The timber frames, intrinsic to the Grade II listed charm, had succumbed to the elements, and the once-graceful windows were impaired. The challenge lay in restoring these windows to their former glory without compromising their architectural authenticity.

The Restoration Process

Initial Heritage Assessment

The restoration journey commenced with a comprehensive heritage assessment. Ventrolla collaborated closely with preservation experts to discern the unique features of the sash windows at St Aidan’s School, ensuring that the restoration plan aligned with conservation principles.

Like-for-Like Timber Restoration

Ventrolla’s craftsmen embarked on a meticulous restoration of the sash windows. Rotten timber, carefully routed out of the original box frames and sills, was replaced with new like-for-like timber. This ensured that the distinctive features of the windows were preserved, revitalising the elegance of the Grade II listed frames.

Cord Replacement and Pulley Servicing

The restoration extended beyond aesthetics. Sash cords, worn with time, were replaced to ensure smooth and safe window operation. Pulleys, essential to the historic design, underwent careful servicing to revive their functionality, contributing to the seamless operation of the restored sash windows.

Balancing Act for Smooth Operation

To ensure the windows were not only aesthetically restored but also functionally efficient, Ventrolla performed a balancing act. The sashes were correctly balanced, guaranteeing smooth operation and safeguarding the safety of the windows for generations to come.

Preserving Heritage Amidst Modernization

Conservation-Driven Approach

Ventrolla’s restoration process was underpinned by a commitment to conservation. The use of like-for-like timber, adherence to conservation guidelines, and a meticulous approach to detail were central to ensuring that the windows retained their historical authenticity.

Seamless Integration of Modern Functionality

While preserving historical features, Ventrolla seamlessly integrated modern functionality. The replacement of rotted timber and the meticulous balance adjustments did not compromise the integrity of the Grade II listed windows but, instead, enhanced their operational efficiency.

Results and Impact

A Restored Legacy, Functional Brilliance

The restoration of the six sash windows at St Aidan’s School resulted in transformative outcomes:

  • Preservation of Architectural Legacy: The meticulous restoration preserved the architectural legacy of St. Aidan’s School. The sash windows, once marred by decay, emerged as eloquent testaments to the Grade II listed grandeur of the institution.
  • Functional Brilliance: The integration of modern solutions ensured that the restored windows operated with a newfound brilliance. The replacement of rotted timber, cord replacement, and pulley servicing contributed to the functional efficiency of the sash windows.
  • Extended Lifespan: The restoration efforts not only addressed immediate concerns but also extended the lifespan of the sash windows. The use of like-for-like timber and careful balancing ensured that the windows were poised for enduring service.


Following the renovation process, the unique Ventrolla Perimeter Sealing System (VPSS) was installed to combat draughts and reduce external noise, making the classrooms a more comfortable environment.

Robert Holmes, St. Aidan’s building manager, said:

“The windows were in a very poor condition this time last year, making it very unpleasant during both the summer and winter. When you needed air to circulate they wouldn’t open and when you wanted to keep warm they would let draughts in.”

Thanks to Ventrolla this was all resolved, making a huge difference in comfort without affecting the characteristics of this beautiful period building.”

“They were very accommodating throughout the project, with work taking place out of term time, and finished on time to a high standard.


Ventrolla’s restoration of forty-six sash windows at St Aidan’s School in Harrogate stands as a harmonious blend of heritage preservation and modern ingenuity. This unique case study unfolds as a testament to the delicate artistry required to revive historical elements while nurturing contemporary functionality. St. Aidan’s School, with its revitalised sash windows, not only stands as a custodian of history but also beckons future generations to witness the seamless fusion of the past and present.


St. Aidan’s High School in Harrogate, North Yorkshire was established in 1968. It now caters to 2000 students and is extremely proud of its academic achievements after being named the top mixed non-selective school in the country for A-A* grades by The Times and The Daily Telegraph.

Ventrolla offers a bespoke renovation service for timber sliding sash and casement windows, as well as timber doors. The company has its central office in Harrogate, North Yorkshire, with additional locations throughout the UK.

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