Tilda Swinton wants to live in a glass box for a week.

The Oscar-winning actress slept in the clear container for eight hours a day, seven days a week as an exhibition piece at the Serpentine Gallery in 1995, and, although she got shingles because of the stunt, she would love to do it again.

She said: "I still want to make that piece again. I was very ill for five months after it. And I do think it had something to do with the strain of endurance… of being looked at by 22,000 people over the course of a week."

Tilda had wanted to return to the box when she was pregnant with her 11-year-old twins, Xavier and Honor, but ruled it out after deciding it could be "a little dicey".

Meanwhile, Tilda has revealed her open relationship is "the best thing" for her children.

The 48-year-old Scottish actress lives with her partner John Byrne and the twins but also has a romantic relationship with artist Sandro Kopp.

Swinton said: "It may seem odd but it is certainly the best thing for the children.

"It's not something I try to promote as a radical lifestyle choice. But it's a situation I find very healthy. I can maintain my life with my children and their father and spend time with the man I've become very fond of.

"I am very fortunate there has been a lot of understanding by the men."