Do we need consent from the council to update the 1970s kitchen in our listed cottage?

Replacing a kitchen would not normally require consent so long as there is minimal impact on the fabric of the listed building. When replacing wiring and plumbing, it is important to reuse existing routes as far as possible, avoid damage to original features and to install new services in a way that will allow them to be easily maintained. However, if in doubt, check with your local authority.