Designer Tania Handelsmann created this Sydney, Australia, home for her friends. Located on a lush path, just 10 minutes from Sydney's CBD, Woollahra House is carefully tucked into a jungle sanctuary that blends with the fascinating urban context.

Designing a treehouse is an intimate interior design process for Tania Handelsmann, a childhood friend she met in kindergarten. Tania admires her old friend's bold personality and adds "a subtle dose of luxury" to the family. The simple leather material is satisfied by precise details and the perfect tension of oak flooring, plush carpets and luxurious fabrics. "We escheted the usual Australian jungle vernacular in favor of bold monochrome '80s designs, creating a high-low aesthetic and practical luxury," Tania says. On a practical level, this is for entertainment and low maintenance surfaces.

The '80s aesthetic first reminds you of puffy sleeves and shoulder pads. Instead, it was the iconic designer of the era, Andree Putman, and her decadent style, tempered by restraint and "rich geometry with warm sensuality," that inspired the house's objects. The coveted works of Pierre Jeannette, Gerrit Rietveld, Josef Hoffman and Eileen Grey make up the decades-long design style of the 20th century, along with contemporary customised works such as the marble dining table "Verde Chambery".