>carriage?
Could be the guest house.
Taxpayers spend $2.5-million for reconstruction of guest cottage at PM’s Harrington Lake retreat
"The “Caretaker’s House” originally built in 1850, has been renamed the “Farmhouse,” and is currently being used by the Trudeau family while $6.1-million in restoration work is being done to the main cottage, a country home for Canadian prime ministers since the late 1950s.
Restoration of the 16-room main cottage, that sits on secluded Harrington Lake, has been suspended because of the COVID-19 outbreak, according to Jean Wolff, a spokesman for the National Capital Commission (NCC) that manages the government’s official residences in the capital region."
https://www.theglobeandmail.com/politics/article-taxpayers-spend-25-million-for-reconstruction-of-guest-cottage-at/