Granary and corn crib, step by step
Interactive lesson: a house for grain — choice and size, site, posts with rat guards, building the granary, the corn crib, filling and upkeep.
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The whole lesson as text
1. Granary or crib
A granary stores dry grain; a crib dries and stores maize on the cob.
- Granary for dry grain — Wheat, rye, barley, oats and dry beans go into the granary dry, at no more than 13–14 % moisture.
- Crib for cobs — Maize on the cob dries in the crib, from 25–35 % moisture at harvest to 14–15 % in spring.
- How much space — For 1,000 kg of wheat roughly 1.3 m³, plus 20 % empty space at the top. For a crib, 3 L per kg of grain. 1 m³ is about 35 cubic feet.
- A full granary is heavy — One metre of wheat presses roughly 770 kg on every m² of floor (about 160 lb per sq ft). Bays higher than 1.5 m (5 ft) and buildings for more than 3–4 tonnes need a carpenter or structural engineer.
Why: A granary is closed, so grain must go into it already dry. A crib is open: the maize only dries in it. That's why the two buildings are built completely differently.
- If you have less than 1,000 kg of grain, a granary rarely pays: a galvanised bin or a few drums in a cool larder are easier to clean and close.
- A crib pays from 300–500 kg of maize, because it saves drying.
2. The site
The site is half the job.
- Dry and well drained — Never in a hollow, by a stream or where water collects. The ground around the building slopes gently away from it.
- The crib in the wind — The long side of the crib runs across the wind that blows most often in autumn and winter. The granary in the shade, on the north or east side of the house.
- Away from trees — Branches, fences and roofs closer than 2–3 m (7–10 ft) are a bridge for rodents. Keep at least 15–20 m (50–65 ft) from the muck heap, livestock buildings and compost if you can.
- A mown strip — Keep a strip 1–2 m wide around the building mown short or covered in gravel. Don't stack firewood, planks or old tools against it.
Why: A good granary on a bad site gets damp, rodents and drips. Rodents don't like crossing open ground where a cat or owl can see them.
- A granary and a crib are outbuildings, but planning and building rules can still apply: in the UK check the Planning Portal and your local planning authority, in Ireland your county council, in the US and Canada your county zoning office.
- Close to the house, with access: so you see it every day and can bring a vehicle up with sacks.
3. Posts and rat guards · Locked
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4. The granary step by step · Locked
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5. The corn crib · Locked
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6. Filling and upkeep · Locked
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