The Clement Brooking Steel Window Technical Specification

Product Summary

Developed in collaboration with the Hampstead Garden Suburb Trust and other conservation bodies, the Brooking range of windows takes its name from The Brooking National Collection of historic windows and doors whose Founder, Charles Brooking, is an internationally renowned collector and conservationist.

Providing a traditional appearance, these windows are specifically for use in very sensitive fenestration projects.

Part L Regulations

Can comply with Part L through the centre pane U Value method if Brooking windows are double glazed.

Manufacturing Specification

Made to suit your individual requirements Brooking windows are generally manufactured in accordance with BS 6510:2010 specifications for hot rolled steel windows. The mild steel sections used for Clement window and door frames are precision rolled in Switzerland using only recycled steel to suit Clement’s unique profiles and tolerances. All frames and ancillary profiles are hot dip galvanised to BS EN ISO 1461 and available with a factory applied polyester powder coating to BS EN ISO 13438 from the RAL colour range, exceeding the minimum paint thickness over the zinc of 60 microns.

Manufacturing Description

Frames are manufactured from hot rolled mild steel profiles with corner joints mitred, welded and dressed square and flat. Small panes can be formed with T glazing bars whose ends are tenon riveted and/or welded to the frame and cross joints are interlocked and welded with rigid joints. Composite windows can be assembled by connecting windows horizontally and/or vertically with mullions and/or transoms of hot rolled slim steel profiles. Box sections are available as tubes or as box mullions which can be either hot rolled or manufactured from sheet steel. Pressed metal cills are available in a choice of profiles. Trickle vents can be fitted in accordance with Part F of the Building Regulations.

Locking system

The Brooking range of windows is available with traditional single point locking and other security devices if required.

Fixing

Brooking windows can be fitted into timber subframes, or fixed direct to brickwork, concrete or stone. Windows are fixed either direct or with fixing lugs using stainless steel screws that are appropriate to the structural opening.

Glazing

Brooking can be supplied with various glazing options, from both inside or outside including:

  • Clear glazing
  • Genuine T bars
  • Genuine leaded lights, using real lead that is soldered by hand in a diamond or rectangular pattern in variable widths of lead.

Combinations of fixed lights, top hung, side hung and bottom hung windows are available as well as single and double doors in both ‘open in’ and ‘open out’ configurations.

Brooking windows accommodate single and insulating glass. These GGF approved windows (with proprietary glazing system units to 14mm thickness) are recognised and specified by both Heritage England and The National Trust. Windows may be double glazed to a maximum thickness of 14 mm.

In accordance with Glass & Glazing Federation best practice, Clement steel windows are generally factory glazed, however, our concealed fixings mean that fixed light windows need to be glazed on site after the frames have been installed. Glazing beads are made of aluminium.

Brooking windows can be supplied with semi, round or gothic style heads, and ‘curved on plan’.

Dimensions (Provided for guidance purposes only)

Nominal profile width 25mm
Typical sight lines: fixed lights perimeter: < 37mm
Hinged casements: < 52mm

Windows and doors for composite panels are purpose made, generally within the limits shown in the table below; sizes outside these limits may be discussed with one of our sales consultants.

  Width Height Perimeter
WINDOWS Min (mm) Max (mm) Min (mm) Max (mm) Max (mm)
           
Fixed light 300 2000 300 2000 6800
Top hung 300 1250 300 1300 4600
Side hung 300 650 300 1350 3700
Bottom hung 300 650 300 650 1300
           
DOORS          
Double 900 1200 2000 2100 6600

 

Sound

The average Sound Reduction Index (SRI) of a single glazed unit is approximately 30 dB, but this varies with window type, size and glass thickness.

BS 6375-1:1989

Air permeability was measured in terms of opening joint length (m³/h/m) against progressively increasing test pressures through 200Pa (class A), 300Pa (class B) up to 600Pa (class C). Class B, or a maximum value at 300Pa of about 16 m³/h/m, was the UK standard requirement. Water tightness was measured in resistance to leakage at progressively increasing test pressures, 300Pa being considered the most severe UK requirement. Wind load resistance entailed deflection and gusting tests at pressures ranging from 1200Pa to 2400Pa.

Window Type BS 6375-1 Test Pressure Class 1989 edition
  Air Water Wind BS 6375-1 Exposure Category
         
Fixed light 600 300 2400 2400
Top hung 300 200 2000 2000
Side hung (open out) 300 200 2000 2000
Bottom hung 200 100 1600 1200