Materials

Why we keep coming back to lime plaster

It breathes, it ages beautifully and it makes daylight look softer. A short love letter to the oldest finish in the studio.

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Signe Halvorsen
12 Sep 2026 · 6 min read

Lime plaster is the oldest finish we specify and, most years, the one we specify most. It is made from limestone, burned and slaked, and it hardens by slowly taking carbon dioxide back from the air. In other words, it quietly turns back into stone on your walls.

It breathes

Unlike gypsum or acrylic finishes, lime is vapour-open. Moisture moves through it instead of being trapped behind it, which is why it is essential on old solid walls and wonderful in bathrooms.

Good materials do not need decoration. They need light, time and a little patience.

It makes light softer

Lime has a slightly uneven, mineral surface. Sunlight scatters across it rather than bouncing off, so rooms feel calmer and colours shift gently through the day.

Where we use it

  • Living spaces facing strong southern light
  • Bathrooms and wet rooms, with a tadelakt finish
  • Historic buildings with solid masonry walls

It ages well

A small crack or scuff can be repaired with a brush and a little fresh lime. Over the years the walls develop a patina that no paint can imitate, which is exactly the kind of ageing we design for.

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Signe Halvorsen

Founding partner at Forma. Signe has spent eighteen years designing homes and hotels around daylight, and still sketches every first idea by hand.