Planners will advise families looking to adapt their homes or build wings or extensions for relatives.
Multi generational living is popular on the continent.
In Guernsey, it is seen as a way of reducing the demand for housing, cutting living costs and promoting social interaction.
Typically, elderly parents or grown up children would have their own accommodation as part of the main family home, using outbuildings, wings or adapting the interior.
Planners say that existing policies may mean that development can take place without the need for permission, and they can advise on that.
The head of the Development and Planning Authority, deputy Neil Inder, says this is why the drop in is being held:
"This is one of those areas where people might not realise what they are able to do.
"Even if you're only in the very early stages of thinking about development you might like to carry out, I'd encourage you to come along for a conversation to help you on your way."
Members of the Planning Service will be at the Castel Douzaine Room from 10-12 today, (30 May).

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