Home > Companies > Ventrolla Sash Window Restoration > Secondary Glazing Horizontal Slider Unit

Horizontally sliding secondary glazing available in two, three and four panelled combinations. Can be supplied with arched or gothic head profiles and with stacking units. These units are generally used in conjunction with either sash or casement windows where full access is required and where there is sufficient space internally to open the casement secondary glazing.


Tested and approved to the following British Standards:

  • BS 1474 (Aluminium Alloy).
  • BS 7386 (Polypropylene draught strip).
  • BS 6375-1 (Performance - Water tightness - Test pressure class 300 Pa).
  • BS 5368-1 (Performance - Air permeability - Test pressure class 600 Pa).
  • BS 5821-3 (Acoustic performance - Weighted sound reduction index, minimum Rw 49 dB).
  • BS 6206 (Glazing).
  • BS 2782 (Gaskets).

Standard product features


Aluminium 6063 T6 Alloy to BS 1474.

Weather pile:

Polypropylene draught strip to BS 7386.


  • Water tightness (to BS 6375-1): Test pressure class 300 Pa.
  • Air permeability (to BS 5368-1): Test pressure class 600 Pa.
  • Acoustic performance (to BS 2750-3, BS 5821-3): Weighted sound reduction index, minimum Rw 49 dB.


Product reference:

Available with combinations of two, three or four panels. Two and three panel systems are handed.

Size (w x h, maximum):

  • Two panel: 2400 x 2000 mm.
  • Three panel: 3600 x 2000 mm.
  • Four panel: 4900 x 2000 mm.
  • Five panel: 4900 x 2000 mm.

Frame finish:

Anodized to AA5 - BS 3987 or polyester powder coating to BS 6496 to give a 60 micron high gloss finish. Stock colours are white and van dyke brown, other RAL colours available on request.


Glazing to BS 6206. Available with acoustic glass, clear float glass, laminated glass or toughened glass, all in a range of thicknesses.


Extruded to BS 2782. Standard colour black, white gaskets available on request.


Available with a range of ironmongery.


Hardwood or PVC-U trims colour coded in a range of sizes.

Grounds/ Sub-frames:

Available with hardwood sub-frames to suit standard or reveal fix, or with bay adaptor.


Consult Ventrolla for recommendations and details.

NBS Specification

NBS Create logo
This product is associated with the following NBS Create clause:
45-25-99/310 Aluminium window units

NBS Specification

NBS Buliding logo
This product is associated with the following NBS clauses:

Product specification

An important note about specifying



Ventrolla Sash Window Restoration


+44 (0)1423 859323

Product reference

Secondary Glazing Horizontal Slider Unit


[CO3 Left-hand]
Three-piece horizontal slider.
[CO3 Right-hand]
Three-piece horizontal slider.
[SS2 Left-hand]
Two-piece horizontal slider.
[SS2 Right-hand]
Two-piece horizontal slider.
Three-piece horizontal slider.
Four-piece horizontal slider.
Five-piece horizontal slider.


[As drawing]
[As schedule]

Special features

[Not required]
[Arched head]
[Gothic head]
[Stacking units]

Frame finish

[Anodized, natural]
[Polyester powder coating, white]
[Polyester powder coating, van dyke brown]
[Polyester powder coating, RAL]
Special order, insert colour requirement.


[Acoustic glass, 6.4 mm]
[Acoustic glass, 6.8 mm]
[Clear float glass, 4 mm]
[Clear float glass, 6 mm]
[Laminated glass, 6.4 mm]
[Laminated glass, 6.8 mm]
[Toughened glass, 4 mm]
[Toughened glass, 6 mm]




[Barrel lock]
[Budget lock]
[Chubb lock]
[Shoot bolt]
[Restricted opening lock]


 - Material:
 - Size:
[6 x 15 mm D.B.N]
[6 x 33 mm D.B.N]
[6 x 43 mm D.B.N]
[6 x 21 mm S.B.N]
[6 x 27 mm S.B.N]
[6 x 37 mm S.B.N]
[6 x 44 mm S.B.N]
[6 x 55 mm S.B.N]
[6 x 75 mm S.B.N]

Grounds/ Sub-frame

[21 x 45 mm hardwood sub-frame, standard fix]
[21 x 62 mm hardwood sub-frame, reveal fix]
[30 x 30 mm hardwood sub-frame, bay adaptor]
Insert requirement.


[Face fix]
[Reveal fix]

Manufacturer details

Ventrolla House,
Crimple Court,
Hornbeam Business Park,
North Yorkshire, HG2 8PB
Tel +44 (0)1423 859323
Fax +44 (0)1423 859321
NBS Plus