Stockholm design studio TAF has created a sofa for Swedish retailer Svenkst Tenn with a curvaceous form to recreate the comfort and elegance of lying in a roll top bath.

The studio, headed by Mattias Ståhlbom and Gabriella Gustafson, was asked by Svenkst Tenn to create a contemporary sofa that would complement its collection of classic 20th-century pieces.

Established in 1924 by Estrid Ericson, the store is best known for producing pieces by Austrian architect Josef Frank, including furniture and a range of colourful fabrics and accessories.

In recent years Svenkst Tenn has collaborated with leading designers to expand its product range. TAF's Famna sofa is the largest item it has developed so far.

The company still produces sofas designed by Frank and his contemporary Björn Trägårdh in the 1930s and 1940s, but their size and style makes them unsuitable for many modern homes.

"They asked us to create a soft and comfortable contemporary sofa that retains the distinctive Svenkst Tenn expression and uses their traditional manufacturing processes," Ståhlbom told Dezeen.

TAF examined people's posture in various scenarios and eventually drew inspiration from the way in which traditional bathtubs embrace and support the user.

"When you sit in an old roll top bath it looks so elegant and also so comfortable because your arms a little higher and you have this rounded surface all around you," Ståhlbom explained.

"That's why we chose the name Famna, which means embrace in English."

The sofa features a low seat height and generous depth that invites users to lounge. Large, pillow-like cushions help the design to invoke the comfort of a bed.

Famna was also influenced by the way Svenkst Tenn's upholstered furniture is made at the O.H. Sjögren factory in the Swedish town of Tranås.

The company, established in 1902, is one of the country's oldest furniture manufacturers and uses traditional techniques to craft pieces for several Swedish brands.

"The way they produce furniture using hand craftsmanship makes it possible to create curves that are more complex than you would draw if you were designing for mass production," said Ståhlbom.

"We were able to design a form with curves in several dimensions that looks good from all angles, including from behind," he added.

"It takes a week to produce one sofa, but it is incredibly durable so it will last forever."

The sofa's wooden frame is assembled using a method similar to boat building.

Intersecting pieces forming a solid structure that is fitted with pocket springs.

TAF considered how the shape and proportions would suit being upholstered in some of Josef Frank's iconic fabrics, which typically feature large, colourful patterns inspired by nature.

The sofa's legs are made from solid beech wood in a range of finishes chosen to match the most popular fabric options.

All of the cushions are the same size so they can be easily rearranged and stacked to reduce the seat's depth if required.

A matching stool is also available.

TAF, which was founded by Ståhlbom and Gustafson in 2002, has also made a light shaped like a poster tube for Swedish brand Zero, and a table with an upside-down frame for Danish company Hay.