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Lift-out secondary glazing units, designed for applications where limited access to the primary window is required. Units fit into a secured channel and consideration should be given to overall sash sizes to ensure the weight of glass is of manageable proportions. Each sash is manufactured with a double brush pile seal, which further increases the thermal and sound properties.

Can be supplied with arched or gothic head profiles and as stacking units. These units are used where the primary window is fixed or where a customer seldom requires access to open the window for ventilation.


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 47 dB).
  • BS 6206 (Glazing).
  • BS 2782 (Gaskets).

General information

As drawing

As schedule

Uniclass 2015
Aluminium window units (Pr_30_59_98_02)Primary
Specification data - Aluminium window units
Product Reference

Secondary Glazing Lift Out Units



Balanced vertical slider.


Tilt-In balanced vertical slider.


Vertical 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






Chubb locks

Flitch locks

Restricted opening locks

Trims -




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 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


Face fix

Reveal fix

Standard product features


Aluminium 6063 T6 Alloy to BS 1474.

Weather pile:

Polypropylene draught strip to BS 7386.


Supplied with standard ironmongery.


  • 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 47 dB.

Product Options

Size (w x h, maximum):

2000 x 2000 mm. Uprated specifications can be obtained on application to accommodate larger sizes.

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, 4 mm white gaskets available on request.


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.

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