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Series 20 Slimline Vertical Sliding

Series 20 Slimline Vertical Sliding

Selectaglaze Ltd

Slimline framing system ideal for treating traditional sash windows often found in heritage properties. Operated with spring balances which support the weight of the sash in all positions.

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+44 (0)1727 837271 www.selectaglaze.co.uk

Slimline vertical sliding (VS) secondary glazing unit in two or three pane sliding sash options. Contra-sliding panes provide access to the primary windows for cleaning and maintenance.

Sashes cannot be removed. A minimum frame gap of 75 mm is recommended.

Sashes slide within the frame so do not interfere with blinds or curtains. Twin brush seals ensure high sealing efficiency. All fixings are concealed within the frame, which may be linked to other frames with a colour-matched mullion/ transom section.

Will reduce heat loss by up to 50% using standard glass and up to 65% with a thermally efficient glass (low emissivity).

Suitable for listed buildings where the primary glazing cannot be changed. It is a reversible adaptation, so generally accepted by heritage agencies.

Thermal performance:

U-values as low as 1.8 W/m²K (timber primary window and low-E glass in secondary glazing).


  • Acoustic: Tested in accordance with BS EN ISO 140-3: 1995 for acoustic performance. Between 39 and 46 dB can be achieved.
  • Blast tested to ISO 16933 Classification code EXV 45.

General information

As drawing

Insert details.

As schedule

Insert details.


Twin compression seals, concealed fixings, can be coupled to other units with colour matched aluminium alloy transom/ mullion, adjustable spring balances, curved frame head available


Extruded aluminium alloy 6063-T6


Ten year manufacturers guarantee subject to Selectaglaze terms and conditions. Five year on spring and spiral balances

Uniclass 2015
Ss_25_60_35_65 Putty-fronted single glazing systemsPrimary

L10/58 Secondary glazing system

L10/580 Secondary glazing system

Specification data - Putty-fronted single glazing systems
Product Reference

Series 20 Slimline Vertical Sliding (VS)


As primary window designs/ sightlines

Vertical sliding, two pane

Vertical sliding, three pane


As drawing

Insert details.

As schedule

Insert details.

Acoustic performance

Insert required dB level.

Thermal performance

See 'Options' below and insert requirements.

Blast performance

Not required

ISO 16933 EXV 45

Frame -
Frame finish

Anodizing, Analok bronze AA25

Anodizing, Analok silver AA10

Polyester powder-coating, HIPCA 9910 semi-gloss white

Polyester powder-coating, RAL

Insert RAL colour.

Wood grain effect

Gloss level

Not required

High gloss



Glazing -


Laminated, low-E


Toughened, low-E


4 mm

6 mm

6.4 mm

6.8 mm

Glazing gasket



Ironmongery -

H3 Recessed finger pull, colour matched to frame


H17 Cranked D handle, colour matched to frame


Not required

L2 fitch catch (lockable), white

L2 fitch catch (lockable), black

L2 fitch catch (lockable), gold

L2 fitch catch (lockable), polished chrome

L2 fitch catch (lockable), brushed steel

L4 plunge lock, silver

L13 S10/20 sliding latch

Trickle ventilators

Not required

Over the frame standard ventilator

Over the frame acoustic ventilator

Acoustic reveal linings

Not required

Vinyl faced acoustic foam

Standard product features


- Material:

Extruded aluminium alloy 6063-T6.

Product Options


Sash height to width ratio should not normally exceed 1:3. Maximum sash area subject to 20 kg weight capacity.

  • Sash, minimum (h x w): 300 x 350 mm.
  • Sash, maximum (h x w): 1500 x 1400 mm.
  • Curved head or jamb minimum radius: 450 mm.

Thermal performance:

Values of <2.9 W/m²K available; consult manufacturer for details.

Digital objects
PlatformCompatibleVersionCertified to
IFC2X3 2 1.3
Revit 2015 2 1.3
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