Answer: Burpee currently offers a booklet with plans for several types of frames. A web search using "coldframe plans" as the search term will also yield numerous sets of plans both on-line and for purchase. In general, a coldframe should be located out of the wind in a sheltered spot. Traditionally they face south to maximize the sunlight. You can make a simple one out of strawbales covered with a storm window, but in my experience it is really helpful to have one with a hinged lid that can be opened and closed by a temperature sensitive venter.
Below are two references you may find helpful in deciding how and where to build yours.
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