Design principles

Unique modular design

Our design principles

We have developed a unique, modular design and build process that means we can deliver a fast yet bespoke solution for every client.

We place the highest importance on using high quality, sustainably sourced materials, twinned with beautiful design, to create an efficient, low carbon ARC building. All of our design decisions are based on balancing the embodied carbon and long-term efficiency and performance of the building.

We design and build in ‘pod’ sections which are optimally designed for transportation, for a smooth offsite-to-onsite transition. We have a tried-and-tested approach using our unique modular components to design and build a range of different ARC building sizes and configurations that we flex to each and every client requirement.

Our key design elements

Let us take you through some of the key elements of our ARC buildings.
Also see our ARC I and ARC II pages for further information.


The ARC is a timber, CNC* engineered building manufactured using sustainably sourced, FSC certified structural panelised timber.

The curved, core structure is precision manufactured using CNC* manufactured OSB3, with a birch plywood outer skin.

The timber structure sits on a simple steel sub-frame which sits on the foundation system. Within the ARC II there are also internal steel columns for structural support that also enable the building to be craned from connection points above and below the building.

*CNC – computer numerical control

Insulation and airtightness

Maintaining high levels of insulation in our ARC buildings is crucial and delivers a thermally efficient building.

We use 220mm in multiple layers of carbon negative, recycled wood fibre insulation, which gives excellent U values that far exceed building regulations.

We use internal vapour control layers within the structure to prevent condensation and act as an airtight barrier to improve the building’s energy performance.

We also use high-quality airtightness tape to ensure all joints are completely secured to maintain excellent airtightness levels.


The standard roof finish of our ARC buildings is a sedum-based green roof that helps to insulate the building, keeping it warm in the winter and cool in the summer. The green roof also promotes biodiversity as it is a natural habitat for pollinators, and performs carbon sinking.

Below the green roof, we have a highly efficient, multi-layer roof membrane system that is water, wind and root proof, and backed with a 25 year warranty.

We also offer a curved solar PV roof option.

Windows and doorways

The custom-curved glazed ends are a beautiful design feature of our ARC buildings that allow plenty of natural light to penetrate into the building. We offer options for solar shading, if required.

We also offer a range of other window options for the rest of the building – including wall, roof, mansard, and picture windows – and will design window layouts to best optimise the space and any external views.

Triple glazed doorways can be designed into the glazed ends or within the rest of the building, as required.

We only use triple glazed windows, glazed ends, and doorways, which minimises heat loss and thermal bridging.

External cladding

Our standard external finish is a sustainably sourced Poplar, which undergoes a unique heat treatment to ensure excellent durability. Over time the cladding turns a soft ‘silvery’ colour through natural external exposure. We are happy to discuss other external cladding options, as required.

There is a discreet shadow gap on the external cladding between ‘pod sections’.

Flooring and walls

We usually use a painted internal cladding that follows the ARC building’s curved profile to offer a comforting, yet unique, interior finish. Other internal wall finishes can include wall panels and fabric finishes. We have various tiling options available for kitchens and bathrooms/WCs.

Different flooring options are available, such as engineered-timber, vinyl or carpet.

Mechanical and electrical

ARC buildings are usually heated with underfloor heating, and we use LED lighting as standard throughout our buildings.

Smart technology can also be incorporated throughout the buildings, for example to control a number of comfort factors such as heating, lighting, security.

On larger projects with high occupation levels – such as cafés, retail, visitor centres and classrooms – we will discuss ventilation options using mechanical ventilation with heat recovery (MVHR), which recovers heat from warm, stale air and delivers fresh, filtered air inside.


We encourage using renewable energy sources wherever possible!

Solar panels or heat pumps (air or ground source) are the most common options available.

Contact us

Speak to the team

01865 682707

[email protected]

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