55mm System proven to Kitemark standards. A choice of profiles and hardware enable this product to be used in a wide range of domestic and commercial situations.

Available in the following range of Colours (click to expand):


This specification defines materials, construction finish and hardware for the “Alitherm” 55 Polyamide casement window, which conforms generally with BS 4873 specification for aluminium alloy windows. Windows described in this specification are suitable for both the replacement windows into the existing building and installation into new building work.


Aluminium: AlMgSi 0.5 Type 6060/6063 T5 in condition F22 (according to NBN P21-001 and DIN 1725)
Sealings: E.P.D.M. according to DIN 7863, TV 110, NFP 85301, ISO 3994. Tested and approved according to an artificial ageing test of “Plexi glass” combined with vulcanised rubber.
Co-extruded profiles: according to DIN 7863, TV 110, BFP 85301, ISO 3994, tested and approved according to an artificial ageing test of “Plexi glass” combined with vulcanised rubber.
Thermal break: polyamide strips PA 6.6.25% reinforced with glass fibre.
Radiation barrier: polyamide strips PA 6.6.25% reinforced with glass fibre.


Electrostatic Powder coating: according to the guidelines of A..P.A.-Qualicoat in most of the current RAL-colours.
The composed profiles (with thermal break) can be coated with different inner and outer colours (single colour).
Anodisation in satin or bronze colours with EWAA/EURAS-Qualinod quality label.
Glass shall conform to the requirements of BS 6262 and part N of the Building Regulations for Thickness and Type.
Profiles and gaskets will accommodate double glazed units of thickness 28mm


Frame members are mitre cut at 45 degrees and faces coated with a suitable gap sealer using internal extruded aluminium corner cleats together with a gluing compound.
Members are abutted and securely jointed by mechanical or crimped means.
Transoms and mullions are end milled to shape and mechanically secured to frame members by means of self tapping screws driven in screw receptacles in the profile or by means of internal cleats.
All mechanical joints shall be sealed against entry of water.
All fixings used in construction shall be either stainless steel, aluminium alloy or other suitable corrosion resistant materials.


All opening vents are hung on concealed stainless steel variable angled friction stays and fitted with espagnolette type locking handles.
To limit the opening restrictor stays shall be fitted.


Aluminium clip in beads and flexible gaskets inside and out meeting the requirements of BS 6262, Code of Practice for Glazing for Buildings.


Test Report 3823, date 11.06.03. Windows having been tested in accordance with the requirements of BS6375 Pt 1 have achieved the following classification for weather tightness:-
Air permeability Class C 600pa
Water Tightness 600pa
Wind Resistance 2400pa

Product Range

Windows are manufactured to required design to within maximum limitations.

Contact us in Leckhampton, Cheltenham, to discover more about our windows and other glazing supplies.