Closed-loop construction

Research, Feature design, Materials, Planning

Designing bespoke materials for a new house within the South Downs National Park.

Chalk cores from site investigations

Streat Hill Farmhouse will be a new 600m2 building, the highest house in the South Downs National Park. The construction will use as much site-based material as possible, including both excavation waste (chalk) and masonry rubble from an original 1950’s fire damaged building.

We are working alongside the design and construction teams to develop bespoke materials for the new house using the site-based waste. We audit the quantities and qualities of materials and prototype new, bespoke finishes and features such as internal plasterwork, brick mortars, flooring and hard landscaping products.

South Downs Way

The design for the new materials will be strongly influenced by traditional vernacular mortars of Sussex, using lime (from burnt chalk) as the binder. Lime mortars have many benefits, including longevity, flexibility and breathability. They are great for incorporating other waste materials and they can be carbon neutral and endlessly recyclable. Conforming to historic and modern ideas of a closed-loop system (circular economy).

Chalk plaster samples
Chalk plaster samples
Lime render sample

Throughout this project we will refer to core circular economy design principles, which consider the whole life of any material and how the value and primary use of any object can be retained for as long as possible.

Our design principles:

  • Keep all materials on site & in use and in original state for as long as possible.
  • Observe waste hierarchy – maintain, repair, retain, reuse, repurpose before recycling.
  • Prioritise careful deconstruction, sorting & storage, over quick demolition and waste.
  • Design for ease of disassembly & cyclical rebuilding.
  • Avoid permanently mixing different materials.
  • Use modular construction & components that can be readily repaired or replaced without deconstructing the whole.
  • Design components at a scale that makes best use of available small dimension waste materials & that can be easily dismantled for future reuse.
  • Make services easily accessible & repairable.
  • Design for adaptability & flexible use.
  • Specify materials & features for simple maintenance & repair, done with on-site skills & tools where possible.
  • Eliminate unnecessary materials, layers & processes.
  • Celebrate materials & make components visible and legible.
Chalk construction in early 20th century South East England

Project: Closed-loop construction

Collaborators:Baker Brown, Elliott Wood structural engineers

Location: South Downs National Park

Date: 2020 – ongoing