insulated sectional steel door model 5255

Key Product Features:

  • Polyurethane insulation, R-Value*=16.22
  • Max Width 26’2”
  • 1-7/8” Section Thickness
  • Continuous steel strips for hinge attachment
  • Stucco embossed exterior with pinstripes

IECC® Compliant

The ThermoMark 5255 meets IECC® requirements for maximum U-Factor of operable fenestrations (2015 Section C402.4) with a 3rd party certified tested value of less than 0.37. ThermoMark 5255 also meets the ASHRAE 90.1 and IECC® requirement for maximum air leakage for fenestration assemblies (2015 Section C402.5.2 Garage doors) with a 3rd party certified tested value of less than 0.40.

Color Options

Embossed Stucco with Pinstriping

door color white stucco

door color almond stucco

door color taupe stucco

door color brown stucco


Custom Colors Available

Garage Door Painting

This commercial door model is available with the TruChoice™ Color System, Wayne Dalton’s custom painting process that offers more than 6,000+ colors.

Window Options:

window options for insulated sectional steel doors model 5155
For flush doors, Thermolite double insulated SSB set in a 2-piece high impact polymer frame.
Optional DSB 1/4" acrylic also available.
41” wide x 15” high and will be available with color matched frame

Materials & Construction

The ThermoMark 5255 features hot-dipped galvanized steel construction that is pre-painted prior to manufacturing with a two-coat system of polyester paint with a finished coat (includes primer). The inside and outside skins are roll-formed and separated with a thermal break to eliminate thermal conductance. Hinge locations have 20-gauge continuous back up plates for fastening. The bottom astragal is a two-piece “bulb” type astragal to be attached to the interior skin. Section ends have end caps of 18 gauge hot-dipped galvanized steel, and a between-section joint seal is standard.

*Wayne Dalton uses a calculated door section R-Value for insulated doors.

door construction of steel door