'Cob' construction is widespread in Devon. It has been used for 4-500 years and is enjoying a resurgence as being very 'green.' It is an inert fireproof material and it has excellent thermal properties. Wikipedia and www.devonearthbuilding.com both provide an excellent summary of the techniques and materials. 

Special consideration and care needs to be taken in assessing whether your cob buildings sum insured is adequate. The sum insured needs to include the costs of removing debris, demolition, professional fees and meeting building regulations requirements as well as building materials and labour. 

Due to the requirement for specialist building skills the sum insured will be higher than for a standard building, especially if it is a Listed Property.

At NFU Mutual we recommend that you obtain a professional valuation by an experienced Cob surveyor if you are in any doubt as to the adequacy of your rebuilding sum insured. If your sum insured is too low then the most your insurer will pay is the rebuilding cost shown on your schedule and they may either reduce your claim to allow for wear and tear, or will reduce the overall claim by the degree of underinsurance.

Check your own insurance policy schedule and wordings for details and contact your advisor if in any doubts. If you haven’t done so already, tell them that your property is Cob straightaway. Keep your property well maintained and repair any minor damage as soon as it occurs since cob properties are more susceptible to damage from ingress of water. As cob needs to 'breathe' problems can also arise where impermeable renders have been used rather than the more flexible traditional lime based renders.