Interior design firm Studio Giancarlo Valle has turned an early 20th-century cinema in Stockholm into a showroom for rug company Nordic Knots, restoring its original stone details and adding warm wood and brushed steel.

Mottled green marble covers the walls of the 150-square-metre showroom, which is located in the central Östermalm area of Stockholm.

As part of the revamp Studio Giancarlo Valle restored the existing marble – a traditional Swedish type of stone called Kolmårdsmarmor – as well as the building's grand central staircase.

The studio also added more contemporary touches, such as brushed stainless-steel details and walnut and oak furniture.

"The interior is historic and we wanted to preserve the architectural details, so we restored the terrazzo and plaster," studio founder Giancarlo Valle told Dezeen.

"The building is a 20th-century former movie theatre and it was critical to maintain a sense of grandness when entering the space," he added.

Nordic Knots' co-founder Liza Laserow wanted the interior to feature as many of the original details in the 1918 building as possible.

"During the demolition of some old closets, we discovered the original floor to the building from the early 1900s – a muted green terrazzo with a red and white checkerboard," Laserow told Dezeen.

"Discovering the original flooring made us realise that we wanted to use terrazzo throughout, as the green colour in the original terrazzo matched the green marble on the walls perfectly."

The brand managed to find a Swedish company that could replicate the original terrazzo to cover the entire floor area.

The stone floors and walls are complemented by a variety of natural materials.

"To balance out the existing stone and terrazzo, we brought in warmer, more tactile materials like pine, oak, and walnut," Valle said.

Oak and walnut shelves decorate the walls of the Sample Bar, a room where customers can see samples of different Nordic Knots rugs, and where Studio Giancarlo Valle introduced custom-made oak lounge chairs.

Valle also added brushed-steel touches to the Nordic Knots showroom, including on its custom-made steel and walnut coffee bar in the main gallery area and a table in the Sample Bar.

The furniture throughout is designed in reference to the building, such as the curved front of the coffee bar that reflects the shape of its doorposts.

Laserow and co-founder Fabian Berglund had previously worked with Valle on a series of rugs for the company, which resulted in four designs, including an all-beige rug with a pattern of open hands and a red rug with flower buds on it.

These are used to decorate the walls and floors of the showroom.

At the back of the building sit the company's meeting rooms and office spaces, which feature wooden furniture and a colour palette of saturated blues and mustard yellows.

"The new interiors very much honour the building's history," Valle said.

"We were careful to preserve the historic architectural details, along with the feeling of entering a grand theatre, when designing the space."

The showroom opened during this year's edition of Stockholm Design Week, which also featured an exhibition of "functional art" by Danish studio Tableau and a virtual apartment.

Studio Giancarlo Valle's designs have previously been used for projects including a showroom in a Brooklyn warehouse and a co-working company founded by Yves Béhar.

The photography is courtesy of Nordic Knots.