This architectural designer's elegant home is a lesson in harnessing contrasts

It has taken over 30 years, but the architectural designer Charles Rutherfoord and his partner Rupert Tyler have finally acquired the last bit of a south London house that was once carved up into six flats

A previous permutation of their living quarters was featured in House & Garden in July 2004, after they had reintegrated the first and second floors. Last year, Charles and Rupert bought the raised ground floor - the final piece of the puzzle. While one side of this floor is used as Charles's office, the other is now a dining room at the front and a kitchen at the back. The rich, tobacco-coloured walls and formal arrangement of furniture and artwork in the dining room sits in stark contrast to the minimalist kitchen and its wall of sliding glass doors.

These doors lead to a terrace overlooking the garden, which is something that has kept Charles and Rupert so attached to the house over the years. It really is magnificent, and in terms of its size and its style, so unusual for a London garden. Charles's eyes light up when he talks about it - even details such as the new shelving in the greenhouse, where seedlings, succulents and subtropicals grow. Upstairs, the main bathroom also has its own terrace that makes the most of this view.

For the past seven years, he and Rupert have participated in the NGS Open Gardens scheme (of which Rupert is a trustee), in which hundreds of visitors come to see thousands of tulips standing tall among irises and tree peonies. Charles refers to himself as a plantsman, preferring the soft structure created through planting to the strict lines created through hard landscaping. It is interesting that a designer whose interiors have such a strong geometry takes such a different approach to his garden designs. But it is another contrast that works so well.

'I am keen for clients to understand the spirit of what I do,' he says. 'There is a stillness to the work, which is an important part of it.' He says it is difficult to capture this in photographs, which is why he often invites clients to visit. And although the Open Gardens programme is strictly outdoors, I think those who do visit might still get a sense of the designer and his work.

Charles Rutherfoord: charlesrutherfoord.net.