A Low‑Impact Passivhaus Set Within a Historic Landscape
Foxcote House is a single‑storey Passivhaus dwelling set within the former kitchen gardens of a Grade II* listed property in rural Northamptonshire. Designed by Clive Chapman Architects under the UK’s ‘country house clause’ planning policy, the project demonstrates how contemporary residential architecture can be sensitively integrated into a historically significant landscape.
The building is partially embedded within its surroundings, reducing visual impact and improving environmental performance. Organised around a sheltered south‑facing courtyard, the home maximises solar gain during winter months while maintaining a strong connection to the landscape through carefully controlled openings.
IQ Glass was appointed to design, supply and install a series of high‑performance sliding glazing systems across the project. These elements form a critical interface between interior living spaces and the central courtyard, while meeting the stringent energy targets required for Passivhaus certification.
Designing Glazing for Passivhaus Performance
Glazing within a Passivhaus building requires a careful balance between transparency and insulation. Large openings are essential to bring daylight deep into the plan and support solar gain, yet they must deliver exceptional thermal performance to minimise heat loss.
At Foxcote House, this challenge was addressed through the specification of triple‑glazed sliding door systems with highly efficient glass compositions and thermally broken aluminium frames. All glazing was engineered to meet strict performance thresholds, contributing to the building’s overall low energy demand and internal comfort.
The positioning of glazing across the south‑facing courtyard plays an additional environmental role, allowing passive solar heating in winter while working in conjunction with shading strategies to limit overheating during summer months.
A Large‑Scale Sliding Door System as a Central Feature
The primary architectural glazing element is a continuous sliding door installation spanning approximately 21 metres along the internal courtyard elevation. This expansive system connects the open plan living, dining and day spaces to the external courtyard, forming a flexible threshold between inside and outside.
Configured as a multi‑track, multi‑panel arrangement, the doors can be opened in a variety of ways, allowing different zones of the house to engage with the courtyard independently. Panels were carefully sized and coordinated with the internal architecture, ensuring that junctions align with structural and finish elements.
Despite the scale of the installation—with individual panels weighing over 500kg—the system maintains slim sightlines and smooth operation, preserving a sense of visual continuity across the façade while delivering the performance required for a Passivhaus envelope.
Extending the Courtyard Connection to Private Spaces
In addition to the main living areas, three further sliding door systems were installed to the ground floor bedrooms, each opening directly onto the central courtyard. These more intimate interventions reinforce the courtyard as the organising element of the house, providing private outlooks while maintaining consistency in material and glazing language.
Each doorset uses a minimal sliding configuration with one fixed and one opening panel, offering a balance between openness, thermal efficiency and ease of use. The repeated application of these systems creates a unified architectural rhythm across the internal courtyard elevations.
Material Integration and Environmental Strategy
All glazing systems were finished in anodised aluminium, selected for durability and its ability to integrate seamlessly with the restrained material palette of the building. The combination of high‑performance glazing, locally sourced materials and passive environmental strategies supports the project’s broader sustainability objectives.
Beyond energy performance, the glazing contributes to the spatial experience of the house. Long views across the courtyard, controlled natural light and direct access to outdoor space create a calm, inward‑focused environment that reflects both the rural context and the architectural intent.
A Contemporary Insertion Within a Historic Setting
Foxcote House demonstrates how advanced glazing technology can support both conservation principles and contemporary environmental design. By integrating large‑format, high‑performance sliding systems within a carefully considered architectural framework, the project achieves a balance between openness and efficiency.
The result is a dwelling that sits quietly within its historic setting while delivering the comfort, clarity and performance expected of a modern Passivhaus.
Project Details
Project Type: Single‑storey Passivhaus dwelling within a historic estate setting
Primary Glazing: Large‑scale slim sliding glass door systems
Main Courtyard Installation:Approx. 21m wide × 2.7m high
Multi‑track, multi‑panel configuration
Maximum panel weight approx. 578kg
Uw value approx. 0.76 W/m²K
Bedroom Glazing:Three additional sliding door systems
Approx. 2.7m wide × 2.5m high each
Uw value approx. 0.95 W/m²K
Glass Specification:Triple‑glazed toughened glass
Low‑emissivity coating (Pilkington Optitherm S1 Plus)
Centre pane Ug value approx. 0.5 W/m²K
Frames: Thermally broken aluminium, anodised finish (C34)
Performance Criteria: Designed to Passivhaus standards
Wind Load: Approx. 0.65 kN/m²
