Converting a rental property - how do I tell current tenants?

[Martha Claypool]

I am in the process of closing on a duplex rental property in the great Cincinnati Ohio area. I plan on renovating the property into a single family in the next few months and would like to notify the current tenants that they will be required to move. Currently they are on month to month leases. Does anyone have a good form to use, and/or recommendations on how to go about this. 

As far as I can tell, these are good tenants, unfortunately the home is not in good enough condition for them to stay. 

Thanks!