Thermally Rated Steel Door

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Steeldor thermal was developed to comply with door efficiency targets stipulated by the government in The Building Regulations 2010. The leaf has an insulated, internal Rockwool core enabling it to achieve a U-value of up to 1.9, compliant with the guidance of 2.0 for new dwellings and 2.2 for new commercial buildings.

These door-sets meet the standards set out in the 2010 approved documents L1A and L2A.

  • Expandable sides as standard
  • Thermally rated Rockwool core
  • Keep the heat in and the cold out
  • Huge range of hardware options avaliable
Unique Range Features

10-14 day lead time
Fast quotes
Easy fit doors
Steel door expert advice

Download Tech Specs
Made in Britain Colour

Product Features

Height Icon

Single - up to 2.96m
Double - up to 2.96m

Width Icon

Single - up to 1.4m
Double - up to 2.7m

Leaf Thickness

44mm deep leaf skin

Air permeability

EN1026:2000 to class 4 – 600Pa (113kmh) test pressure

Water tightness

EN1027:2000 to 150Pa for outward opening and 100Pa for inward

Resistance to wind load

EN12211:2000 to 1200Pa (Class A3) 98 mph

Thermal transmittance

U Value up to 1.9 W/m2K

Weather tightness

BS 6375: Part 1: 2009 (test to EN1026:2000, EN1027:2000, EN12211:2000) to 1200 exposure rating

Further information


Rebate frame
Typical door configuration consists of the standard rebate frame assembly, for either single or double door-sets. Made from lightweight, high tensile ‘Rustec’ steel and powder coat finish, it also has an “Adjust-2-Fit” side expander system that offers 6 adjustable fixing positions. Various frame depths and styles are available - including double rebate frames (see frame specification sheet). Manufactured from 1.6 mm thick ‘Rustec’ steel. Single rebate 104mm wide frame with an additional rebate for the flush lip. A minimum of six fully adjustable fixing points are provided to each jamb - extra fixings available on request. Unique ‘Adjust-2-fit’ side channels with each frame.

44mm door leaf thickness, fitted with a flush lipped astragal for added security. Comprising of 2 x 1.2mm ‘Rustec’ steel sheets, the leaf is internally bonded with a dutch fold stitch welded system providing greater stability and protection against de-lamination. 42mm thick ‘Hexatex’ core or upgrade to Rockwool insulated core. Industrial door threshold - 96mm. The standard aluminium threshold is Part M Compliant and is fitted with a neoprene seal for outward opening door-sets.

40kg/m2 with honeycomb core, excluding hardware and reinforcement 

Door ironmongery
BS 7352 Grade 13 stainless steel, twin bearing template drilled butt hinges with integral high-security dog bolts are fitted as standard with CE marking. Other hardware on request.

Supplied inclusive of a powder-coated finish in a standard colour. Full range of RAL and BS colours available. 

Strongdor self-adhesive P-seal provided as standard.

96mm Door Threshold

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Rockwool Rebate Frame

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Single Door Installation

Single Door Installation

This video contains detailed, step-by-step instructions for the safe installation of a Strongdor Steeldor single door-set. Please pay particular attention to the safety instructions.

Double Door Installation

Double Door Installation

This video contains detailed, step-by-step instructions for the safe installation of a Strongdor Steeldor double door-set. Please pay particular attention to the safety instructions.

Touching Up Paintwork

Touching up Paintwork

A demonstration of how to sue the touch up kit supplied with your steel door-set.

Trimming Expander Panels

Trimming the Expander Panels

Instructions on how to trim the side expander panels, for when the aperture is too tight.

Steeldor Single PD Thermal TS 22 Front Cover

Steeldor Thermal Single Personnel Door

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Steeldor Single EE Therm TS 22 Front Cover

Steeldor Thermal Single Emergency Exit

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Steeldor Double PD Thermal TS 22 Front Cover

Steeldor Thermal Double Personnel Door

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Steeldor Double EE Thermal TS 22 Front Cover

Steeldor Thermal Double Emergency Exit

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Strongdor Steel Frame Door Options 22 Thumnail

Steel Door Frame Options

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Strongdor Over And Side Panel Options Thumbnail

Over & Side Panel Options

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Strongdor Standard Colours 22 Thumbnail

Standard Colours & Coatings

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Door Installation and Maintenance Instructions

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Light & Visibility

Glazed Vision Panels

Our vision panels are produced in various panel formats and sizes, some of which can be fire rated, we offer a choice of glazing options depending on the door's application.

Visibility panels

Door Configurations

Personnel Steel Doors & Emergency Exit Steel Doors

Personnel configs
Emergency Exit configs

Over 150 colours available

View Colour Options

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