DFM DOORS UK

OS Range · Non-standard dimensions

OVERSIZED
STEEL FIRE
DOORS.

Non-standard dimensions. Fire resistant and non-fire resistant options. Single and double leaf. For warehousing, logistics, plant rooms, and industrial applications.

ETA-22/0324· EN 13501-2:2016· EN 1634-1· CE Marked · DoP Issued· ITB · Efectis · KIWA · OiB · RISE· Building Safety Act Ready
Classification Table

OS Range — Fire & Non-Fire Options

Source: ETA-22/0324 (revised May 2024, OiB Vienna, Notified Body 1322). Oversized doorsets are configured to project — classifications below describe the certified variants.

Product Configuration Fire Classification Smoke Classification
OS 60-1 Single leaf · Fire EI 60 Sa4 / S200
OS 60-2 Double leaf · Fire EI 60 Sa4 / S200
OS 00-1 Single leaf · Non-fire Non-fire · CE
OS 00-2 Double leaf · Non-fire Non-fire · CE

Fire-resistant oversized doorsets are classified EI 60 to EN 13501-2 with Sa4/S200 smoke control. Non-fire oversized doorsets are CE marked as standard steel doors. Both variants are available in single and double leaf configurations sized per project opening.

  • Warehousing
  • Logistics
  • Plant rooms
  • Industrial units
  • Data centres
Technical Specifications

Doorset parameters.

Oversized doorsets are configured to project opening. Parameters below are the certified envelope — confirm dimensions, finishes, and ironmongery per schedule.

Maximum single leaf
1600 × 3500 mm — indicative, confirm per project
Maximum double leaf
3200 × 3500 mm — indicative, confirm per project
Leaf construction
Reinforced double-skinned galvanised steel, mineral-wool core, internal bracing for oversized spans
Frame
Reinforced galvanised steel profile · factory-welded mitred corners · anchor pattern sized to leaf mass
Acoustic (Rw)
Up to 38 dB, dependent on configuration
Hinges
Heavy-duty steel hinges — count scales with leaf height and mass (typically 3–4 single, 6–8 double)
Lock
Mortice lock, multipoint option, cylinder to client profile
Door closer
Heavy-duty overhead closer, EN 1154 compliant · sized to leaf mass
Glazing option
Vision panel to EI rating · max 480 × 880 mm
Finish
Powder coat, full RAL palette · Corrosion class C3 (C5 optional, recommended for external non-fire)
Installation

Gap-fill and frame guidance.

Oversized doorsets carry significantly greater leaf mass — anchor pattern, embedment depth, and frame bracing are sized per project. A fire-rated OS doorset is only classified when installed within the conditions set out in the ETA and the project-specific installation schedule.

Supported substrates: masonry, reinforced concrete, and structural steel. Lifting plant is typically required for leaves above 2500 mm height. Intumescent and smoke-control seals on fire variants are factory-fitted and must not be removed or painted over.

Download installation manual →
  • 01

    Verify the opening

    Check structural opening against the dimensions and substrate noted on the order acknowledgement and ETA field of application.

  • 02

    Frame fixing

    Fix frame with approved anchors at centres specified in the installation manual. Plumb, square, and packed to manufacturer tolerance.

  • 03

    Gap-fill

    Fill the perimeter gap with the specified intumescent mortar or mineral-wool product per the ETA field of application. No foam. No generic sealants.

  • 04

    Commission and record

    Hang leaf, test closing and latching, record DoP reference and installer sign-off for the Golden Thread file.

CE Certification

DFM DS doorsets are CE marked for internal applications under ETA-22/0324, issued by OiB Vienna (Notified Body 1322).

For external door applications, contact us to discuss current certification status before specifying.

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