June 23, 2026 / By rachel

Some projects are ahead of their time. This one was so far ahead of its time that part of the job involved explaining what the construction method actually was.

For Week 16 of our 40 Projects in 40 Weeks series, we are revisiting what is believed to be the first SIPs house in the UK, a pioneering timber frame project designed by RRA Architects with Oakwrights in 2000.

Today, Structural Insulated Panels, or SIPs, are a well-established construction method. Back then, they were new, unfamiliar and definitely not something most people in the UK housing market were casually chatting about over coffee.
This was new territory; exciting, innovative and just a little bit nerve-racking.

A client who wanted something different

The client wanted a bespoke timber frame house, but not a traditional one. So, RRA Architects worked with the clients and Oakwrights, then a relatively young timber frame company founded by Tim Crump, to develop the design. The brief was for something more American in construction, but that would still be English enough in style to sit comfortably in a typical British suburb.
Tim travelled to America to visit Woodhouse, a specialist timber frame company in Pennsylvania, to source the bespoke post and beam frame. The frame was made from slow-grown Douglas fir, shipped to the UK and designed to be assembled on site with every post and beam pre-cut, pre-drilled and numbered.
So far, so ambitious.

Then came the panel

While Tim was in America, he was introduced to a new construction product: Structural Insulated Panels.
He returned to the UK with a small sample piece of SIP panel in his luggage and kept it in his kitchen for a couple of months.
The client loved the idea of using this innovative system and the project moved forward with RRA Architects and Oakwrights designing what is believed to be the first SIPs house in the UK.
But that small sample panel did not just influence one house.
Jeff Tomlinson from Kingspan happened to be visiting Tim and saw the sample panel and asked to borrow it. When Jeff returned the sample a few months later, he declared that Kingspan had bought a company in Germany manufacturing SIP panels.
From that small sample, a much bigger chain of events began, eventually leading to Kingspan TEK becoming a major name in structural insulated panel construction.

Working across the pond, before Zoom was a thing

Designing the first SIPs house in the UK was not a simple case of sending a few files across by email and jumping on a video call.
In 2000, the internet was still finding its feet. Connections were slow, file sizes needed to be tiny, Zoom was still just a car noise and Teams meant the people sitting around you.
Much of the coordination happened by phone, across time zones, with RRA and Oakwrights working between UK metric measurements and American imperial measurements. Which would have been annoying enough on a simple rectangular box, but this house was not a simple rectangular box.
At its centre was an octagonal atrium, with a staircase following the geometry of the space and a complex roof structure above. RRA had recently moved from drawing boards to computers, but the software was still clunky and file storage was limited. This was architecture with floppy disks, patience and a lot of careful checking.

The complicated roof

Mark Powles, now RRA’s Managing Director, was a young architect at the time working on the detailed drawings for the project. One of the biggest challenges was the octagonal centre of the building, with its staircase, roof pitches and complex timber frame geometry. The entire frame was being manufactured in America, so every dimension, junction and detail needed to be right before the timber was cut, drilled, numbered and shipped to site.
That is quite a lot of pressure when the building is effectively arriving as a giant, very expensive timber flat-pack. Mark remembers being extremely nervous as the frame arrived, was unwrapped, craned into position and bolted together. Understandably. Nobody wants to be the person watching a life-sized wooden Meccano set fail to line up.
But it did line up, it lined up beautifully. For a building of that complexity, and with so many unusual challenges for the time, that was a remarkable result.

From pioneering project to established industry

The clients were delighted with the finished house and the project remains a memorable example of what can happen when a client, architect and specialist manufacturer are all willing to try something new. It is also fascinating to look at the wider story now.
Oakwrights has grown from a relatively new company into one of the UK’s leading timber frame specialists. Its Elements division now designs and manufactures high-performance timber frame systems, including pre-insulated wall and roof panel systems, with a fabric-first approach focused on airtightness, insulation and thermal performance.
In other words, what felt experimental in 2000 is now part of a much bigger conversation about energy efficiency, off-site construction and sustainable building.

Still part of the RRA story

The first SIPs house in the UK is one of those projects that feels even more interesting with hindsight.
At the time, it was a technical challenge, a design challenge and a coordination challenge. Looking back, it was also a small part of a much bigger shift in how homes could be designed and built.
There was a client willing to try something different, a young Oakwrights pushing timber frame construction forward, a sample panel in a kitchen and a RRA team carefully working through complex details before the days of easy file sharing and video calls.
Thankfully, the giant timber frame fitted together beautifully.

You can read more of the project on the full project page here.

Thank you to Tim Crump of Oakwrights for kindly sharing his memories of this groundbreaking project with us and to Savills and the current owners for their kind permission to use the photos.

About RRA Architects

Currently celebrating its 40th year, RRA Architects is an award-winning architectural practice established in 1986, supporting clients across residential, commercial, retail, development, heritage, education, community and conservation projects.
We work nationally, but are mostly focused across Gloucestershire, Herefordshire, Shropshire, Worcestershire, the Cotswolds, Bristol and Avon, the West Midlands, South West and South Wales, helping clients create thoughtful, practical and well-designed buildings.