The prospect of beach living conjures up the image of relaxing seaside hideaways, but for the team charged with the design and construction of two houses on the beach at Camber Sands, the site’s seaside location was anything but calming.

The wide bay supports the only sand dune system in East Sussex. The marram grass-capped dunes, which fringe the bay, were formed from sand blown inland. And the sand presented several challenges in the design and construction of the units.

The location at the foot of the dunes also made construction difficult because the contractor had to find a way to get materials to the site, which was accessible only by crossing the soft sands of the public beach.

Architect and designer Stuart Martin, of the Walker and Martin practice (WAM), worked with consulting engineer Fluid Structures to design the two houses, and timber was fundamental.

"The scheme is intended to give a low-impact construction solution, which treads lightly on the beach, and to use materials and techniques that support this approach," he said.

The materials also had to be light, rigid and, more importantly, easily transportable so they could be moved across the beach to the site. "I wanted to assess an option for off-site construction that could be easily dismantled and reassembled on site owing to the limited and difficult site access we had across a public beach," said Mr Martin.

WAM’s design for the site is a striking solution for two identical rectangular houses, each measuring 8x20m and topped by a gabled engineered timber roof and first-floor structure. The buildings’ pitched timber roofs are free of any internal supporting structure to enable two bedrooms to be accommodated in the roof void. The structure also had to span the width of the ground floor to ensure it remained open-plan and column-free.

Metsä Wood technical experts worked alongside the design team to ensure the optimum engineered timber solution was developed for the A-frame portal roof and the floor structure. The team used Finnframe software’s advanced design package to turn the concept into a detailed specification that complies with British and European standards.

Finnframe software allowed the beach house roof and floor designs to be viewed in 3D as well as plan view; it delivers clear material listings and structural and assembly drawings to save time and eliminate waste. "Metsä provided the Kerto LVL solution and technical expertise and back-up to the product," said Mr Martin.

The scheme also used Building Information Modelling (BIM) software to demonstrate Metsä Wood’s capacity and capability of developing a scheme in this collaborative working environment. BIM embeds key product and asset data into a 3D computer model that can be used for management of information throughout a project.

The timber design developed for Camber Sands is based on using Metsä Wood’s Kerto suite of products for the trusses and decking. The A-frame roof is fabricated from Metsä Wood’s Kerto S beams. Kerto S is manufactured with the wood grain in the veneers running longitudinally through all the layers to provide excellent strength, dimensional precision and stability. The trusses are set at 1200mm centres.

"Kerto S is an ideal choice for beams whenever lightweight, long spans and minimal deflections are required," said Metsä Wood senior engineer Ewa Ostrowska.

Daniel Saunders, of specialist sub-contractor Crendon Timber Engineering which fabricated and installed the Kerto elements, concurs. "The use of Kerto S meant we were able to design to a high specification and keep the member sizes within the desired sectional sizes for aesthetically pleasing feature trusses," he said.

Metsä Wood’s Kerto Q was used for the roof and floor decks. Kerto Q is a cross-bonded veneer, with one-fifth of the veneers glued cross-wise to improve the lateral bending strength and stiffness of the timber element to enhance its shear strength. The cross-bonded veneers also help reduce moisture-dependent variations across the width of the panel.

"Stability is provided by portal action of the A-frames in plane along with the diaphragm action of a Kerto Q deck at roof and first floor level," explained Gerard Doyle, senior engineer at Fluid Structures.

The timber roof structure rests on reinforced concrete walls comprising 100mm insulation; 250mm concrete, strengthened using A393 reinforcing mesh; and 50mm internal insulation. The cast concrete solution was chosen in preference to blockwork, which would have had to be braced throughout construction and be designed to accommodate loading from sand drifting against the walls.

To minimise the buildings’ visual impact and to give the seaside houses "a beach hut feel" they are clad in timber too.

"The method of construction was chosen in order to provide a robust solution that could be constructed easily given the site conditions," said Mr Doyle.

Each house is built on a 250mm-thick concrete raft foundation, formed on a stone sub-base to ensure minimum bearing pressure on the beach.

"Using insulated concrete formwork and Metsä Wood’s Kerto system provided a solution that eased the construction process and potentially speeded-up the onsite process consequently minimising the environmental impact to the beach," said Mr Martin.