Because the gambrel roof doesn t go very high above the brickwork you can discover that you do not have enough living space in your attic.
Insulating a gambrel roof room.
Interview with the contractor at the end.
How to vent a gambrel roof using reflectix.
If you have an existing house with this style then dense pack cellulose or pour in place open cell foam are your only options.
To insulate the roof you will need to use a combination of insulation to fully protect the roof.
If you do not want any extra living space in your attic then you can install a low height roof but you will also have a small space to install the insulation and the ventilation system.
There is no access into the small sidewall areas and thus must be accessed by drilling holes in the sidewalls in this case the roof and using dense pack of poured foam methods to properly insulate.
This should be a must see video for venting a gambrel r.