Porthmadog House mines the rich seam of Wales’ industrial past at the Dwyryd estuary

North Wales is famously home to Portmeirion, the Italianate-style village beloved by King Charles and the set of the cult 1960s television series The Prisoner. But just a stone’s throw away on the Dwyryd estuary, in Porthmadog, is an altogether more contemporary proposition: this striking new build by Ström Architects, an award-winning Hampshire-based practice founded in 2010.

Step inside this Porthmadog House

Joining a string of beautiful contemporary homes hiding in the Welsh countryside, by the likes of John Pawson and Loyn and Co, Porthmadog House was designed by founder Magnus Ström as a forever home for a newly retired couple. It is the latest addition to a portfolio including a white house on Stockholm’s coast, in Ström’s native Sweden, and a woodland retreat in the New Forest, and a Case Study-inspired home in Gloucestershire.

Set between Irish Sea and estuary, the 475 sq m home features two slate-clad volumes topped by a corten-clad upper floor. It is the result of long research from the owners, who spent five years carefully curating inspiration before approaching Ström at the end of 2019. The couple decided to build on a site that they knew well: the former property had once belonged to a childhood friend, but had been left derelict for 15 years.

‘Overall, this was never a project about speed,’ says Ström. ‘It was about control, patience and staying rigorously aligned with the original vision from first sketch to final build. The aim was always to create something with a genuine sense of permanence, not just visual impact.’ Perfectly answering his clients’ brief, the house is warm, comfortable, with a design that maximises both sea and estuary views and is deeply connected to its setting.

Set on a sloping site between the Irish Sea and the estuary, the house was designed to create ‘a sense of permanence and protection’, withstand the harsh local weather and provide shelter from the coastal winds. Ström Architects mapped wind, rain, and sightlines to determine the building’s form, as well as terraces that seamlessly connect indoor and outdoor living.

‘Technically, the exposed location introduced real complexity,’ says Ström. ‘Wind, driving rain, and increased structural loading influenced everything from form to detailing. This required close coordination with Jensen Hunt, the structural engineers, who worked alongside us to resolve these pressures without compromising the architectural intent. There was also sustained collaboration with the contractor, fabricators and stonemasons, all of whom played a critical role in achieving the required level of precision and craft.’

The finished design, perfectly poised on the site, also highlights the architect’s pared-back approach. ‘The site demanded restraint where instinct often pushes for drama,’ explains Ström. ‘The temptation to over-open views or over-articulate the form had to be constantly reined in to preserve the calm, grounded nature of the house. That sense of quiet confidence is harder to achieve than something overtly expressive. It requires discipline and a willingness to hold back.’

The street-facing elevation reveals very little of the light-filled rooms and vistas inside. With heavy slate walls providing privacy and shelter, the ground-floor volumes act as natural windbreaks, shaping a sheltered entrance courtyard, and hiding cosy rooms, including a snug and a gym lit up by natural light from a Japanese-inspired courtyard.

In between, the open-plan kitchen, dining and living areas boast floor-to-ceiling glazing opening up on the ever-changing views of the estuary and its tides. Engineered timber by Havwoods softens the spaces, while bespoke oak joinery, crafted in collaboration with Rozen and Christian Paul, brings tactile refinement to the kitchen and keeps daily life effortlessly tidy.

Housing a series of bedrooms, the first-floor Corten steel structure extends to create sheltered terraces below. Restrained but confident, its angled form is as much about practicality as aesthetics. The steel fins provide weather protection, solar shading, and privacy, while still perfectly framing the panorama.

‘The vertical fins give the elevation a quiet rhythm and depth that shifts throughout the day. They soften the scale of the upper volume while creating a subtle filter between inside and out, explains Ström. ‘From certain angles the building appears solid and protective, from others, more permeable and refined. That ambiguity is intentional and important.’

Equally important is the choice of material, a combination of slate and Corten steel that reflects both the country’s historic industries and geology: ‘Slate was a deliberate choice,’ says Ström. ‘The house sits on slate bedrock, and using a nearby quarry reinforced a direct connection to its setting. This was about grounding the building in its own territory, allowing it to feel inherently part of the landscape. Porthmadog’s identity is rooted in slate. The town grew through quarrying and export, shaping its economy, architecture and infrastructure.’

‘There is a historical symmetry in this pairing,’ he continues. ‘Steel fabrication in the region developed to support the slate industry, providing the machinery and transport systems that made large-scale quarrying possible. Bringing slate and steel together again felt entirely appropriate, not symbolic but grounded in local reality.’ Not to mention that both materials weather beautifully, deepening the building’s connection to the landscape. The slate’s iron content produces warm orange hues as it oxidises, complementing the rich, rusty tones of the corten above, and the grey-treated cedar that will turn silver gracefully.

‘We wanted to create a home that’s beautiful on day one but becomes even more compelling over time,’ says Ström. ‘The material palette was chosen specifically to achieve that evolution. Welsh slate, corten steel, and cedar were not only selected for their durability but for how they age gracefully. This combination is unique to the project and deeply rooted in the history and context of Porthmadog. Unlike other houses in the area – often white and interchangeable – this home feels truly of its place, designed for its location and nowhere else.’

‘The materials do their job without calling attention to themselves,’ concludes Ström. ‘They carry the history of the place and allow the building to sit with quiet authority.’

stromarchitects.com