An unapologetically theatrical house by Beata Heuman from the archive

One of the pleasures of walking London's residential streets is looking at the front gardens and peering into the windows to glimpse the rooms within. The tall garden fences surrounding this house in the south-west of the city permit no such inspection, so there is a frisson of excitement upon entering into its atmosphere of gentle privacy.

The first sight is of a box hedge arranged in pretty patterns around an old olive tree, its gnarled trunk a thick, sculptural twist from which splay fronds of delicate silver-green leaves. 'The right side of the house was built in the late 1800s and the left was added later,' explains Beata Heuman, the interior designer who, together with Groves Natcheva Architects, is responsible for its current incarnation. Happily, the recent works, which took two years and were completed in April 2016, left the attractive yellow-brick, villa-style façade, with its handsome sash windows and arched front door, untouched.

These delights are nothing, however, to the sheer sensory pleasure of the interior - a highly original space, unapologetically theatrical and oozing energy. 'The owners are both artists. They have quite wild tastes and they love strong colours,' says Beata. 'I was told by the wife that her childhood dream was to have a house with a series of rooms each with its own distinct personality - Chinese, Japanese, American and so on. That would have been too much, but I did want to give the house variation and changes of mood.' This inversion of the usual dynamic - clients requiring encouragement to embrace bold decorative concepts - was an early characteristic of the project. 'It is one thing looking at something and thinking it is cool. It is very different living with it,' says Beata. 'I wanted the house to be fun and uplifting, but also comfortable and not too "full on".'

The owners approached the architectural side of the project with similar verve. 'They had a strong vision for a mix of formal and informal spaces to suit a growing family, as well as an artist's studio and areas for entertaining and for solitude,' explains Murray Groves of Groves Natcheva. 'Over the years, the house had suffered a number of ill-considered adaptations, which left the internal layout compromised. It was clear we needed a single move that would unlock its potential and allow us to reshape it for the family's needs.' The answer was relocating the staircase to the centre of the house. This gave Groves Natcheva an anchor around which they were able to arrange rooms with some freedom, and allowed them to create a grand entrance with views of the well-established rear garden.

Beata's challenge was then to furnish the three-storey, five-bedroom house from scratch, keeping it true to the personalities of the owners. 'We didn't want it to be obvious they had used an interior designer, so I created a layered look that appears to have been built over time.' The owners' large and varied collection of art added an important visual texture to the decoration.

Artworks aside, the scheme is created with pieces from a wide variety of sources. 'It was important that it didn't look as if everything was bought from the same place,' says Beata. There are also many wonderful bespoke items that Beata designed herself, and inventive specialist paint effects, such as the blue base overlaid with five coats of glaze applied to the walls of the ground floor, which, though it barely appears blue, gives a remarkable feeling of depth.

The overall effect is intoxicating, and the owners are understandably thrilled. 'It has been an amazing project,' says Beata. 'Having the opportunity to be this creative is very unusual'.

Beata Heuman: 020-3304 3872; beataheuman.com

Groves Natcheva Architects: 020-7937 7772; grovesnatcheva.com