Aaron, A Trillium
, like most fibreglass trailers can only be considered a three season trailer. There are some manufactures, like Bigfoot
, that offer double paned windows
, and extra insulation for winter use.
Trilliums have a fibreglass shell, and less then 1/2" inch of a foam insulation, which has a lower R value then the equivalent thickness of fibreglass insulation. It is mostly to keep the condensation down. The furnace
is rated at 7000 BTU, but that is likely optimistic.
I have slept in my Trillium
at -17°C. I was cold.