from
The Collaborative International Dictionary of English v.0.48
carriage house \carriage house\ n.
a small building usually near a large residence or part of an
estate, used for keeping coaches, carriages, or other
vehicles; -- also called {coach house}. It is now (1998)
obsolescent and its function has been taken over by the
garage, which is usually attached to a residence or main
building. Carriage houses are still found on older estates,
though not usually used for their original purpose.
[PJC]