OVERVIEW
This case study highlights the successful installation of a horizontal ground source heat pump (GSHP) system in a historic 18th-century Cotswold house. The property, set within 12 acres of gardens and grounds, is known for its symmetrical Georgian architecture, and had been in the same family for over a century. The new owners sought an energy-efficient heating solution that preserved the building’s character while reducing reliance on fossil fuels. A GSHP system was chosen to meet the demands of the 6,600 sq. ft. home and its period features, which required careful planning and execution.
CHALLENGES
Preservation of Heritage: Being a listed property, modifications to the house and its surroundings needed to comply with stringent planning regulations. The heating system could not disrupt the architectural integrity or involve intrusive internal installations.
Large Heating Demand: The expansive house, with its high ceilings and single-glazed windows, required a system capable of providing consistent and efficient heating for multiple zones.
Outdoor Space Utilisation: The property featured ridge and furrow fields, a historically significant agricultural feature that needed to be preserved during the groundworks. To minimise disturbance, a trenching machine was used instead of standard excavation equipment. This approach ensured precise placement of the collector pipes while protecting the unique topography of the grounds.
Mature Landscaping: The 12-acre grounds contained mature gardens, trees, and lawns. The installation needed to avoid damage to these features, requiring careful planning of collector loop placement.
SOLUTION
A horizontal ground source heat pump system was selected as the ideal solution for this property, combining sustainability, efficiency, and minimal visual impact.
System Design: Two Mastertherm heat pumps were specified to meet the heating and hot water requirements of the home. The system was designed to supply underfloor heating in some zones and radiators in others, ensuring compatibility with the new heating infrastructure.
Horizontal Collector Installation: The horizontal collector loops were installed in trenches approximately 1.2m deep, spanning an area of 1,200m² within the property’s grounds. To protect the ridge and furrow fields, a trenching machine was used for precise and minimally invasive excavation. The loops were laid with care to avoid altering the historical landscape.
Heating Distribution: Existing emitter system has been upgraded to operate efficiently at lower flow temperatures compatible with the GSHP.
Hot Water: A 800L high-gain cylinder was installed to ensure an adequate supply of hot water for the household.
IMPLEMENTATION
Groundworks: Excavation for the horizontal collector loops was completed using a trenching machine, ensuring that the ridge and furrow topography was preserved. Excavated areas were reinstated to match the existing landscape, leaving the grounds visually undisturbed.
Heat Pump Installation: The heat pump was installed in an outbuilding adjacent to the main house to reduce noise and protect the unit from weather exposure. System Integration: The GSHP was seamlessly integrated with the newly upgraded heating infrastructure, ensuring efficient operation, and retaining the period charm of the property.
Commissioning and Handover: The system was thoroughly tested and commissioned to ensure optimal performance. A detailed user guide was provided to the homeowners, along with a maintenance plan.
OUTCOME
Energy Efficiency: The GSHP system reduced the property’s heating bills by approximately 50% compared to the previous oil-fired system.
Carbon Savings: The switch to renewable energy significantly reduced the household’s carbon footprint, contributing to the sustainability of the historic property.
Comfort: The system provided consistent warmth throughout the home, even during the colder months, ensuring the house remained comfortable without compromising its heritage features.
Aesthetic Preservation: The installation was completed with no visible impact on the exterior of the house or its historic interiors, aligning with heritage preservation requirements.
CONCLUSION
This project demonstrates how a modern heating solution can be successfully integrated into a historic property. The horizontal ground source heat pump system not only meets the heating needs of this 18th-century Cotswold house but also enhances its sustainability and long-term viability. The use of specialised equipment, such as the trenching machine, ensured the preservation of historically significant ridge and furrow fields, highlighting the compatibility of renewable energy solutions with heritage conservation.
