I also think it is an ash, but a very sick one. I'd even suspect that the previous owners cut away the dead parts before selling.
An example of 3 of these trees with the same issue:
https://www.google.ca/maps/@50.91508...7i13312!8i6656
When I bought the ash for my last house they sold me one that wasn't affected by the disease. (Patmore Ash) Since then I found that the Patmore Ash seems to be more expensive than the other varieties.