Over grown trees with severe ivy growing

The tree outside of my house on council land is growing excessively and is now causing shade in my back garden on a morning. It didn't use to do this and now is causing me a great deal of stress as I can no longer use the garden effectively in the summer month mornings. The tree is also experiencing a large amount of ivy growth around the tree which is beginning to cause concern. I have had the property developer look at this and he says that this appears that it could cause a problem.