A New Field
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Recipe

Cob (earth, sand, straw)

A traditional building material mixed from clay-rich soil, sharp sand and straw. Scaled down for small objects and garden ornaments.

Every A New Field recipe has been run in a domestic kitchen or community hall. Read the safety notes before you start and adapt for your venue.

What you’ll make

Dense, rough, lightly warm-toned. Slow to dry, but very strong when cured.

Flexible slots (flex around your material)

  • Clay

    Clay (mineral)1 part

    Plastic mineral earth. Air-dries to a hard solid, holds shape wet.

    Examples Clay soil

  • Aggregate

    Sand / grit2 parts

    Inert granular mineral. Stiffens clay bodies and cob.

    Examples Builder's sand, beach sand

    Note — Rinse sea sand first.

  • Reinforcement

    Straw / chaffEnough to bind

    Long dry plant fibres. Reinforces cob and earth-based bricks.

    Examples Wheat straw, grass, bramble

    Note — Chop short for small objects.

Fixed ingredients

  • Water · Variable

Equipment

  • Bucket
  • tarp or old sheet
  • bare feet or spade.

Refinements and variations

  • Mix ratios around one part clay, two parts sand, plus enough straw to bind.

Source notes

Traditional earth building; adapted for household-scale making.