The Float House – When engineering and architecture shape each other

Narinda, Phil and their two children previously lived on a traditional canal boat and wanted to move to a new home within the same houseboat cooperative – 35 boats moored at the same site. 

“We live on the canal because we want to be surrounded by nature and we love the calmness of the water. But more importantly, we wanted something that was a family home,” says Narida.

A traditional canal boat sits low, with the floor below the waterline. This one needed to be warm and well ventilated, sit above the waterline, and be easily accessible – seamlessly tying together water and land, inside and outside. 

"The garden is key to us," says Narinda, "because it connects the farmland with the horses coming through to the garden and then through to the water.” 

What the family also wished for was a house with clean lines, high ceilings and big windows.

This way of building, and this type of houseboat, had never been done before. Phil and Narinda put everything on the line – and placed their complete trust in their friend and architect, Paul Colfer of TiggColl Architects.

Most of the Float House is prefabricated, and the logistics – since two low bridges ruled out floating it in as a finished structure – were solved by splitting the hull into ten interlocking steel modules. They were floated into place on the water, while the superstructure arrived as a kit of parts. The roof was one of the elements that wasn't prefabricated. “That was down to skilled labor from the subcontractor's supply chain”, explains Paul. “They brought the material to site, bonded it and fixed it to the roof and the superstructure.”

The width of the Float House was locked to four meters. To gain extra floor space, TiggColl let two bays – for the beds and the kitchen – project out towards the land. That gain came with a consequence for the whole volume of the building. A higher building was considered at first. But once physics and fluid dynamics took over the drawing board, together with the marine engineer, the conclusion went the other way and created an asymmetric form of the roof.

By reducing the vertical center of gravity, it fits into its surroundings a lot better as well. A wonderful case of the engineering forming the architecture and the architecture forming the engineering – a very symbiotic relationship between the two professions.

The facade is clad in untreated Accoya, fixed horizontally with gaps between the boards so the framing behind is visible – a deliberate choice to make the facade read as breathable rather than fully enclosed. The Accoya weathers by silvering and graying with time and GreenCoat^® color coated steel from SSAB was the natural counterpart. “We wanted it to act as a bit of a juxtaposition to the facade," says Paul. "We want the roof to stay crisp and have longevity while the material underneath it weathers.” 

Paul names two reasons for the GreenCoat^®: its durability and resilience in a waterside location, and the subcontractors' prior experience with the product. He says the contractors preferred working with GreenCoat^®, because they were able to achieve the thin, crisp eaves and gable end lines that the architecture required. 

The color choice – Anthracite Grey – refers directly to the canal boats surrounding the house. The detailing between roof and facade was decisive for the whole expression. The GreenCoat^® roof overhangs the timber facade with a slim 50 mm protrusion to keep it watertight and concealed gutters are tucked behind the facade into a ventilation gap. Forming the concealed gutters was, according to Paul, surprisingly straightforward for the workers on site, and the rhythm of the standing seam turned out "quite consistent, straight, and just a very, very crisp outcome." The same logic governed the bays. For continuity, they too were clad in GreenCoat^®, on both the sides and the top. 

TiggColl hopes the solution can be repeated elsewhere. "We would absolutely love the Float House to become a prototype for waterside living," says Paul, pointing to sites across the UK, Ireland and Europe that are beautiful but hard to reach, and could become sustainable communities on water. At the same time, he is careful to underline who drove the project: "The Float House is very much client driven. It was their idea, their dream. We just enabled it."

For Narinda, the build process – nine months in one of the garden's outbuildings before the family could move in, with up to twenty tradespeople on site seven days a week – was anything but an architectural thought experiment.

"We were all sleeping in one room, living in one room. I was cooking in the garden in freezing temperatures. I was like a snowman outside, cooking on a barbecue with a slow oven," says Narinda. The risk was real, and financial. "We don't have the luxury of having money in reserve if it had gone wrong," says Narinda. "It was literally on us. If we'd messed it up, that was it."

But the result speaks for itself and Narinda doesn't hesitate when summing up with a big smile: "I wake up every day and I'm grateful. This is not for everyone, but it's perfect for us."