Here is a few pictures of one of mine;

http://www.thegardenersalmanac.co.uk/Data/Coldframe/Coldframes.htm

Click on pictures to enlarge!

Note the patent glazing that allows the removal of the glass in summer.

Made from the glazing bars of an old aluminium greenhouse.

The base inside is lined with removable pallets which can be propped up high in the early part of the season and lowered as the contents increase in height!

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