What kind of door suits a Minneapolis garage?
Most people start with insulation. Insulated doors have a layer of foam between steel skins. Polystyrene foam is the lighter option, and polyurethane foam is denser and usually has a higher rating. R-values for garage door sections commonly run from about R-6 to R-18 or higher, depending on the product. Those numbers describe the door section, not the whole installed door, so gaps and weak seals can lower the result.
When insulation pays off
Insulation is most useful when the garage is heated, when it shares a wall with the house or when a room sits above it. In an unheated detached garage the benefit is smaller, though an insulated steel door is also stiffer, quieter and often more dent-resistant. Windows, carriage-house looks, wood and fiberglass are all options, and each has maintenance trade-offs in a freezing climate.

