System 20 Horizontal Sliding Window


Horizontal sliding windows designed with attractive clean lines which will enhance all types of residential and commercial property.


Profiles are extruded from aluminium alloy (6063 T6, T5 or T4 to BS EN 12020-2; 2001 / BS 755-9; 2001). The sections are minimum 60.2 mm deep, and incorporate a polyurethane resin pour-and-cut thermal break. Structural profiles are designed so the maximum deflection of any member will not exceed 1/175 of its span, with no evidence of permanent deformation once the load has been removed.

Joints are square or mitred: corners are secured with stainless steel screws driven into corner-cleat screw port grooves. Joints are sealed using a small gap sealant.

Windows incorporate an internal pressure equalized drainage system with external ‘snap-on' cover caps. Sashes have composite nylon woolpile inserts to resist the ingress of water.


With suitable glazing, windows can contribute to meeting the requirements of Building Regulations for conservation of heat and power; consult Metal Technology for recommendations and details.

The windows provide Class III weather tightness as defined by BS 6375-1 and BS 5368:

  • Air permeability: 300 Pa.
  • Watertightness; 300 Pa.
  • Wind resistance: 2400 Pa.


Lugs and/ or frame anchors used to secure windows to the building structure must accommodate predicted loads and deflection within design tolerances. Generally, fixings must be positioned 150 mm from each corner and each mullion/ transom, and at centres not exceeding 600 mm. Fixing lugs/ straps should be used only where they can be suitably concealed.

General information


As drawing ___

As schedule ___

Uniclass 2015

Pr_30_59_98_02 Aluminium window unitsPrimary


L10/25 Aluminium windows

L10/330 Aluminium windows

Specification data - Aluminium window units

Product Reference

System 20 Horizontal Sliding


As drawing ___

As schedule ___

Glazing details

6 mm single glazing

24 mm insulating glass units

Ironmongery/ Accessories

Manufacturer’s standard

Product Options


Limiting dimensions for opening vents:

  • Maximum height: 1500 mm.
  • Minimum width: 600 mm.
  • Maximum width: 1500 mm.
  • Maximum weight: 80 kg.

Configuration and ironmongery may also limit sizes; consult Metal Technology technical department for details.

Finish as delivered:

Polyester powder coated to BS 6496: consult Metal Technology for availability of colours and to obtain samples.


Windows can accommodate 6 mm single glazing and 24 mm insulating glass units. Windows are factory glazed using wrap-around ‘U’ gaskets fitted around the glass units prior to assembly. Gaskets are joined and sealed at the top-centre of each glazed panel. Consult Metal Technology for recommendation and details.

Ironmongery/ Accessories:

Sliding sashes roll on adjustable rollers, which support the sash in any opening position, and are fitted with self-engaging pull handles with locking cylinder (ref: HS123).

Consult Metal Technology for details of additional ironmongery options.

Similar products from Metal Technology Ltd