case study
The Windmill
The Windmill at Blackthorn, a listed building renovation
Project Overview
Project Name: The Windmill at Blackthorn
Location: Oxfordshire, UK
Type of Property: Grade II Listed Building
Explore our listed building renovation of a 300-year-old Grade II windmill in Oxfordshire, featuring a stunning subterranean extension. The Windmill at Blackthorn is situated in the picturesque Oxfordshire countryside just outside Bicester and features a boutique let at the top of the tower and a luxury, private living space below for the owners. The tower, originally converted into a residential property by its previous owners, provides unenviable views of the Oxfordshire countryside but limited living space for long term habitation. To enhance the functionality and comfort of the property while preserving its historical significance, the project aimed to create a modern subterranean living space beneath the existing windmill tower.
Objectives and Goals
The primary goal of the project was to significantly expand the living space of the windmill by excavating beneath the existing structure. This extension would provide a contemporary, spacious environment that complements the unique character of the windmill while addressing the limitations of the original tower conversion. Key challenges included the need to maintain the structural integrity of the windmill, manage the constraints of working with a listed building, and overcome the spatial limitations of the existing tower.
Scope of Work
The project involved excavating below the windmill to create a 2000-square-metre living space for the new owners. This ambitious endeavour required meticulous planning and coordination among architects, structural engineers, consultants, and a team of highly skilled tradespeople.
Key Materials and Technologies:
- On-Site Stone Harvesting: All stone for the extension was harvested on-site from the excavation, allowing the extension to harmonise with the natural aesthetic of the windmill and its surroundings.
- Waterproofing and Water Tanking: To protect the new subterranean space, extensive waterproofing was carried out, including water tanking of the perimeter walls and roof.
- Structural Support: A ring beam was installed to support the existing tower and form the roof of the new structure.
- Living Garden Roof: The roof of the new extension was designed to support a living garden, providing a seamless transition from the windmill to the landscape.
Challenges and Solutions
As with any renovation of a historical building, the project faced numerous unexpected challenges. These included maintaining the structural integrity of the windmill during excavation, managing water ingress due to the below-ground nature of the new space, and sourcing and working with materials in a way that respected the windmill’s heritage. Overcoming the challenges of this project demonstrates the strength of Jackson Builders collaborative approach to each project.
Experience it yourself.
One of Oxfordshire’s quirkiest stays (Oxford Mail) and featured in The Times newspaper as one of the ‘UK’s best unique stays’, you can book to stay at the top of Windmill and experience unenviable views of the Oxfordshire countryside: Book here
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read moreAs a Fellow of the Royal Institution of Chartered Surveyors, with over 40 years experience in property matters I am happy to put my name forward as a satisfied customer of Jackson Builders.
- Graham Anker FRICS
Oxfordshire
We worked with Jackson Builders on a large refurbishment project in central Oxford. From the off their work was impressive, detailed costings, a schedule, and a great response rate. Their work standard throughout the project was great and they kept on top of all snagging at every stage. Their project management skills are great and the trades employed are all knowledgeable, polite, actually they're fun too. A great team to work with! HIGHLY recommend!
-Niki Schafer Interior Design
Oxford
Jackson Builders have completed a number of projects for us including our kitchen extension. The team are always polite, friendly, trustworthy, and most importantly do a great job. They are experienced builders and are client focused, always on hand to answer any queries you may have. Would definitely recommend.
-Wendy Williams
Oxfordshire
As a Fellow of the Royal Institution of Chartered Surveyors, with over 40 years experience in property matters I am happy to put my name forward as a satisfied customer of Jackson Builders.
- Graham Anker FRICS
Oxfordshire
We worked with Jackson Builders on a large refurbishment project in central Oxford. From the off their work was impressive, detailed costings, a schedule, and a great response rate. Their work standard throughout the project was great and they kept on top of all snagging at every stage. Their project management skills are great and the trades employed are all knowledgeable, polite, actually they're fun too. A great team to work with! HIGHLY recommend!
-Niki Schafer Interior Design
Oxford
Jackson Builders have completed a number of projects for us including our kitchen extension. The team are always polite, friendly, trustworthy, and most importantly do a great job. They are experienced builders and are client focused, always on hand to answer any queries you may have. Would definitely recommend.
-Wendy Williams
Oxfordshire
As a Fellow of the Royal Institution of Chartered Surveyors, with over 40 years experience in property matters I am happy to put my name forward as a satisfied customer of Jackson Builders.
- Graham Anker FRICS
Oxfordshire