The four characterization criteria apply to moats as follows:
- Period (currency): Extended. The moat buildings tradition seems to have lasted for less than 400 years, with a marked peak in building for perhaps a century or so. Although some moats continued in use during post-medieval times there is little evidence for the construction of new sites after the early 16th century.
- Rarity: Abundant. Moats are one of the most numerous classes of medieval monuments known in England. Approximately 6000 sites are known. There are some regional variations in moat distribution, notably the low frequency of recorded examples in western and northern areas.
- Diversity (form): High. The form and size of recorded moats indicates considerable variability within the moat building tradition. At least six main types can be recognized on the basis of ground-plan, and within several of these further sub-types can also be identified. No firm chronological or regional variations in type can at present be discerned.
- Period (representativity): Low. Moats are just one of many classes of medieval monument. They are a particular form of residence provided with a water-filled boundary ditch, and as such represent only one component in the range of settlements of the period.
Assigning scores to these criteria following the system set out in the Monument Evaluation Manual, moats yield a Class Importance Value of 20. This lies about one-third of the way up the range of possible values (max= 64). In selecting examples of national importance attention will need to be given to getting a good mix of types and a range of sites in different situations.