Cob: Re: patio walls?

[Christopher Greenslade]

I have have repaired a number of cob walls here in the Uk and all walls must
have a hat! or I should say some form of weather protection.
Slate or tiles are generally used here.
Unless you have really bad weather I would not worry too much able the
exterior rendering, many walled gardens do not have any rendering at all and
wearing by weathering takes a very long time.