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Steel insulated double skinned sectional doors offer the highest levels of insulation for any standard garage door and also have enhanced insulation levels using various optional components and deeper panel models.
We offer various manufacturers on our website. They all have extremely high levels of insulation, measured as a U value.
Carteck Insulated Sectional doors standard thermal transmittance: 1.3 W/(m²·K)
Hormann Insulated LPU42 sectional doors standard thermal transmittance: 1.3 W/(m²·K)
Hormann Insulated LPU67 sectional doors standard thermal transmittance: 1.0 W/(m²·K)
This door with a ThermoFrame system fitted: 0.91 W/(m²·K)
These are just a few examples and are the U valued for a FITTED DOOR, many companies will give you the U values just for the actual panel and not a fully installed door tested and certified.