Home > Companies > Twinfix Limited > In-Line Access Hatch

In-line access hatch panel with 6 mm solid polycarbonate glazing. Comprises three panels in total: two fixed panels (one at the top, one at the bottom, and one removable central panel).

Features and benefits:

  • Can be quickly and easily removed from below without the need for special equipment, enabling full 360° access (through canopy glazing to gutters, and other parts of the roof).
  • Creates a safer system of work for maintenance staff, with no need for scaffolding to be erected close to platform edges.
  • In-line design, which gives a sleek and unobtrusive finish to any roof.
  • Non-fragile.
  • Fast installation.
  • Suitable for use on heritage sites when used with Georgian glazing.
  • Long-lasting, low-maintenance, durable glazing is included, which won’t crack or break due to building or engine movement.
  • Green product, with glazing which may be recycled after use.

Designed for fitting into Twinfix multi-link and bar and sheet systems – consult manufacturer for details.

Standard product features


  • Infill: 6 mm polycarbonate.
  • Frame: Extruded aluminium bars to BS 1474.


Polyester powder coating to BS 6496.

Panel width:

600 mm.

Fire performance:

Class 1Y to BS 476 Part 7: 1997, 'Surface spread of flame'.

Fragility rating:

Panels tested in accordance with ACR[M]001:2014, and Classified 'Class B non-fragile assembly'.

Primary fixings:

Stainless steel self-tapping screws and stainless steel bolts/ nuts as recommended by Twinfix.

Maximum unsupported span:

3200 mm (down the slope), 600 mm (panel width), and up to 1000 mm (removable hatch length).

Loading capacity:

  • Wind: 0.9 kN/m².
  • Snow: 0.5 kN/m².

Maximum unsupported overhang:

150 mm.

Minimum pitch:



  • UV protection: To both sides of the sheet.
  • Sound reduction index: 29 dB.
  • Light transmission: Clear 85%.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-45-00/310 Access panels

NBS Specification

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This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Twinfix Limited


+44 (0)1925 811311

Product reference

In-Line Access Hatch


 - Frame:
[ ______ ]

Infill (polycarbonate)

 - Type:
[6 mm Georgian wired]
[6 mm multiwall]
[6 mm solid]
 - Colour:

Length (removable panel)

[ ______ ]


[Not required]
[Mechanical end plates]
[Ridge flashing]

Manufacturer details

201 Cavendish Place,
Birchwood Park,
Cheshire, WA3 6WU
Tel +44 (0)1925 811311
Fax +44 (0)1925 852955
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