Little update on the project. Previously i had modelled a few items here and there to build a collection of rubble which i can add to. I have now created some rock using the good old fashioned rock gen. Which can be found HERE, you can create low or high poly rocks which depending on how you are going to texture them, can have there UV's laid out easily. These rocks will be used through out the scene as parts of rubble, which will sit along side purpose built objects to fit the scene.