An 18th-century mill in Wiltshire reimagined as a warm family house

Though originally converted in the 1990s, this former mill in a steep-sided Wiltshire valley retained a frustrating layout that made moving through the property awkward. Rising to the challenge, architects David Liddicoat and Sophie Goldhill reconfigured the floorplan and added an extension to create a more coherent space.

The finished extension, constructed in lightweight steel and glass, was inspired by the original agricultural character of the mill and is a distinctive yet harmonious addition. Now, the property is a much more practical space for circulation. 'There is a route that takes you all round the house and, whichever way you turn, you end up outside,' says David. 'It was important that anyone walking through the Old Mill had a sense of it gradually unfolding. It is a surprising space and we wanted to retain that feeling of discovery.'

This effect is underscored by the inverted layout. With the dramatic, high-volume spaces upstairs contrasting with inviting, enclosed rooms downstairs, it quickly became clear that the kitchen and entertaining areas would be better placed in the former and the bedrooms in the latter. There were other factors, too, that David and Sophie considered when drawing up that initial floorplan - primarily, the acoustic changes between the floors. 'We have always been concerned with how design affects all the senses,' says David. 'If you can capture the senses, you end up with an exciting place to live in - we think it's a missed opportunity when people design just for the visual impact. We want you to feel different in different environments. Even if you're in a visually simple building, the textures and aromas can be intoxicating.'

Harriet Whyatt's painting Roma provides the focal point above a vintage chair and table. The cabinets in Farrow & Ball's 'Off-Black' and the sliding room dividers in oak were made by joiners Barn 6 Furniture.

Michael Sinclair

A sculptural staircase connects the kitchen and dining area with the soaring mezzanine level. 'From the first moment we stepped inside, we knew the room demanded a centrepiece on a grand scale,' recalls David. 'We needed something to balance the volume of the space.' The final design was a major technical challenge to construct, made up of two helical pieces that merge together. The team had to corkscrew the parts through the windows to get them into place. Now, the staircase forms a striking focal point that tethers the two upper floors. Stepping down onto the lower floors containing the bedrooms is akin to going below deck on a ship, although those on the ground floor do open straight onto the garden.

When it came to choosing the colours for the decoration, David says cues were taken from existing materials within the building, 'Sophie and I worked closely with the owners, who have backgrounds in painting and interior design, to find a palette that felt natural to the Old Mill.' The lime-plastered walls are painted in Farrow & Ball's 'India Yellow' as a warm balance to the steel and timber structure.

Michael Sinclair

Yellow is a prevalent - yet not dominant - shade throughout, warming up the walls where the steel structures might have made rooms feel a little cold. Red accents on lampshades, rugs and chairs are lifted from the Belgian brick used in the wheelhouse extension. In certain places, the colour is almost that of rusted steel - an apt choice for this historic mill. As David says. 'The real acid test of a building is that, when vou visit it in person, it feels even better than vou had envisaged.' It is a test the Old Mill passes with flying colours.

Liddicoat & Goldhill: liddicoatgoldhill.com