An extensive variety of finishes are available for Graepels Perforated Metal products. Below we have provided information regarding the Anodization process, with a particular focus on Anodized Aluminium.

Anodising is a technique used to modify the surface of a metal. Anodization is frequently used to protect aluminium and titanium from abrasion and corrosion and to allow it to be dyed in a wide range of colours.

Anodized Aluminium

Anodized Aluminium can be found in many Architectural applications due to its aesthetic and corrosion resistant properties. The aluminium-oxide coating is grown from and into the surface of the Aluminium. As a result of this it is not prone to peeling or cracking like organic coatings such as paint.

Please note: Anodising Aluminium must be to grade J57S or equally approved

Benefits of Anodizing Aluminium

  • Anodized Steel has a contemporary aesthetic and finish
  • As the aluminium-oxide coating is grown from and into the surface of the aluminium, it serves to enhance the aesthetics of the aluminium itself
  • The coating is part of the metal itself, therefore, issues such as cracking, blistering and splitting will not occur
  • Anodized Aluminium is resistant to corrosion and is particularly suited to more aggressive environments such as cities and marinas
  • Unlike other metal coatings, Anodized Aluminium gives a uniform and regular finish as it is part of the aluminium itself
  • This finish is environmentally friendly, as it is fully recyclable and the process does not produce CO2 or solvent emissions

Anodising Specification

Perforated Aluminium sheet to outer face of cladding panels example.
  • Perforator Manufacturer: Graepels/ Graepels Perforators & Weavers Ltd/Graepel Perforators Ltd
  • Product Reference: Picture Perf
  • Finish/Colour: Anodised Anolok xxxxx. To be tested on site through prototyping and final colour accepted by project manager
  • Material: Aluminum to be a minimum of 4mm thick, suitable grade for anodising, Grade J57S or better
  • Other: Where possible, aluminum panels for each Facade should be manufactured from a single batch of aluminium. Number of batches of aluminium used per facade to be minimized. If more than one batch is required, batches should be split by floor level.

Anodizing Baths

Baths are a maximum of the following sizes. This may limit the panel size you wish to manufacture.

  • Length: 7000mm
  • Depth: 1250 mm
  • Width: 500mm
Picture-Perf Foyer in Leeds
1 Sovereign Square, Leeds


This case study highlights one of our most impressive Architectural projects. Graepels perforated bespoke Picture-Perf metal panelling for this five-storey foyer in Leeds, UK. The Aluminium panels were anodized in a dark colour, which contrasts strikingly with the lightboxes behind.


All information provided is for guidance only. The Information above is not  comes without warranty or guarantee with respect to the subject matter or fitness for purpose.