Planning Permission granted for hempcrete ecohouse in Bristol

We’re pleased to share that, after two years of persistence, negotiation, and redesign, planning permission has been granted for a new hempcrete eco-home dwelling on a constrained infill site in inner-city Bristol.

Tucked behind a row of terraced homes and accessed via a shared driveway, the previously derelict site will soon be home to a compact, sustainable family house. It reuses the existing garage structure on site and introduces a timber framed house with hempcrete infill, which will be a unique construction in the city of Bristol.

An Eco-Home that Works with Its Site

The project is defined by its responsiveness both to its tricky site constraints and to the environmental challenges facing the built environment today.

The building has been carefully designed to:

• Minimise embodied carbon, using a timber frame construction and hempcrete insulation, a breathable, biogenic material that will store carbon for the lifetime of the building. We have estimated that the walls alone will store 2 tonnes of carbon.

  
  

• Maximise passive solar gain The dwelling is orientated to face exactly south which allows the house to benefit from passive solar gain. Large roof overhangs mean that the house can benefit from heat from the sun in winter whilst minimising direct sunlight on the hottest summer days.

  
  

• Control overheating through the use of louvre system to reduce incoming sunlight in summer. Deep window reveals and thermal mass of both the concrete base and thick hempcrete walls ensures that the home remains comfortable year-round without mechanical cooling.

  
  

• Minimise heat loss through energy conservation and high levels of insulation which far exceed the minimum levels for building regulations. 500mm thick hempcrete walls have a u-value of 0.13W/m2K.

  
  

• Generate its own energy with photovoltaic panels and solar thermal panels installed on the pitched roof positioned to capture maximum solar exposure through the year.

  
  

• Enhance biodiversity on site through two green roofs, located on the stair tower and flat-roofed garage extension. These provide rainwater retention, thermal buffering, and habitat creation, while softening the building’s visual impact.

  
  

• Reuse existing materials, including the former garage structure, to reduce demolition waste and integrate the new home with the memory of the site.

  
  

The design strategy here isn’t just about ticking sustainability boxes, it’s about designing a home that works intelligently with its environment, built for comfort, durability, and low ongoing energy demand. The aim is to create a low-energy house in both the construction and the dwelling's life span.

The Many Benefits of Hempcrete

Hempcrete is a fantastic material choice which provides a myriad of benefits including carbon sequestration, insulation and thermal mass, to fire protection and sound absorbtion. It is unusual for a material to provide the benefits of a "heavy" material like masonry whilst also providing insulation benefits of a 'light' material which can far exceed the levels required by building regulations for a new-build, which makes it a great choice for an eco home such as this one. We will be sourcing the hempcrete from the UK with some of the first ever UK made hempcrete blocks from Ty Mawr in South Wales.

A Small Site, a Big Effort

Despite the home’s modest footprint, the journey to consent was far from simple. Concerns from planning officers included overlooking, privacy, access, and overdevelopment; challenges familiar to many urban infill projects.We engaged in early pre-application discussions, neighbour consultations, and detailed design revisions, working closely with planning officers across multiple submission rounds. The proposal was ultimately approved for its sensitive relationship to context, thoughtful use of materials, and clear sustainability agenda.

Next Steps

We’re preparing to progress into technical design, to develop detailing strategies that deliver on the project’s low-energy ambition.

Construction is expected to begin late 2025, and we look forward to bringing this carefully crafted, low-impact home to life.

If you’re exploring how to unlock difficult urban sites for sustainable living, or want to understand how eco-materials like timber and hempcrete perform in real-world settings, we’d love to hear from you.