The ‘boltless boathouse’ that’s up for an RIBA award

This timber-frame boathouse uses no mechanical fixings in its structure. The boathouse, designed by Ashworth Parkes Architects, was inspired by traditional Japanese temples and ceremonial buildings.

The pagoda-style curved roof is one of several Japanese influences in this elegant small project.

TDUK members Carpenter Oak crafted the frame for this unique building at their Devon yard, and installed it in its idyllic setting by the River Cam. The elegant boathouse is one of 14 projects shortlisted for this year’s RIBA East award.

Fitting square pegs into round holes (literally)
The client, a close friend of the architecture practice, lives in a Grade II listed house with frontage onto the river. They wanted to build it as sustainably as possible, so chose English larch as the main material.

They also didn’t want to include any mechanical fixings in the frame.
This was achieved by using intricate jointing methods that don’t need any screws or nails in the frame. All joints are secured with either drawn round pegs or square pegs in round holes.

Wooden nails and an air gun

To fix the boarding to the roof rafters of the frame, the team used wooden nails which are resin beech and compressed, and are driven in by an air gun. This further avoided the use of mechanical fixings and glue.

The influence of Japanese craftsmanship
There was a very deliberate intention to maintain the spirit of Japanese framing. Clad in a copper roof, the frame takes influence from ‘Sashimono’ and ‘Kumiko’ techniques of furniture building, utilising both simple and complex wooden joinery without the need for nails.

Side view, showing the boathouse’s full length, as it sits on the bank of the River Cam.

Minimising embodied carbon
A repeating structure that minimises the variety of joints, together with use of standard timber sizes and pre-fabrication before moving onto site – all have aided in the reduction of embodied carbon.

Each timber member was carefully marked, assembled and raised over a long weekend between a motley crew of friends.

This article is from issue 3 of Designing Timber magazine. Read more articles from Designing Timber here.