Security Doors

Thermally Rated Steel Doors

From only £495

Based on 800mm x 1900mm

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Key product Features

Door Type

Single, Leaf & Half or Double Dorsets

Acoustic Rating

Up to 36dB

U Value

Single- 1.6 W/m2K, Double - 1.5 W/m2K


1.5mm Rustec Steel

Locking Hardware

Manual and Electronic Locking

Door Leaf Core


Air Permeability

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

Weather Tightness

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

Standard Finish

Range of 150 Stocked Colours

Lead Times

15-20 working days

Why use the Thermally Rated Steel Doors?

When it comes to energy efficiency and security, Thermally Rated Steel Doors from Security Direct are the perfect solution for both internal and external applications. These doors are designed to meet the latest government regulations, including Part L of the updated Building Regulations, ensuring compliance and superior performance. With an insulated Rockwool core, our Steeldor Thermal doors achieve U-values as low as 1.5 W/m2K, making them an excellent choice for enhancing thermal insulation and reducing energy costs.

Our Thermally Rated Steel Doors offer exceptional durability and stability. The 44mm thick door leaf is made from 1.2mm 'Rustec' steel sheets, internally bonded with a dutch fold stitch welded system that prevents de-lamination and ensures long-lasting strength. The frames, constructed from lightweight, high tensile 1.5mm thick 'Rustec' steel, feature the Adjust 2-Fit side expander system, allowing up to 12mm expansion to accommodate various structural openings. This flexibility makes installation easier and more precise.

In addition to their impressive thermal properties, these doors come with a range of customisation options to suit your specific needs. They are available in a variety of sizes, up to 2.96m in height for both single and double door sets, and can be powder coated in any of the 150 standard RAL colors, providing both aesthetic appeal and robust protection. The doors can also be upgraded to include PAS 24: 2016 security ratings, offering enhanced security features such as high-security dog bolts and BS 7352 Grade 13 stainless steel hinges.

Our Thermally Rated Steel Doors also excel in acoustic performance, with ratings up to 39dB, making them suitable for environments where noise reduction is important. They come with standard aluminium thresholds that are Part M compliant and fitted with neoprene seals for outward opening door sets. Additional options include AM3 inward opening and AM5 outward opening thresholds, catering to various installation requirements. For added safety, these doors can be supplied with fire ratings, making them a comprehensive solution for both security and efficiency.

In summary, Security Direct’s Thermally Rated Steel Doors provide a superior blend of energy efficiency, security, and customisation. Whether you are looking to enhance the thermal performance of your building or require robust and secure doors for internal or external use, these doors offer the perfect solution. With fast lead times and a range of options available, investing in Steeldor Thermal means choosing quality and reliability for your building's needs.


44mm door leaf thickness, fitted with an integrated astragal for added security. Comprising of 2 x 1.2mm ‘Rustec’ steel sheets, the leaf skins are mechanically interlocked and internally bonded, providing greater stability and protection against de-lamination. Rockwool Insulated Core.

Manufactured from lightweight, high tensile 1.5 mm thick ‘Rustec’ steel.
Adjust 2-Fit side expander system that offers up to 12mm expansion each side to the structural opening.
Self-adhesive P-seal provided as standard.
Various frame depths and styles are available.

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.

Options and Upgrades
Manual and Electric Locking.
Available as PAS 24: 2016.
Fire Rating

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