Secondary Double Glazing

We have been supplying secondary double glazing to houses flats commercial and listed buildings schools since 1983.

Choose Top quality aluminium secondary double glazing windows by All Purpose Glazing  if you demand:

  • High quality windows. The environmentally friendly materials that we use are robust and durable. Our secondary double glazing last for years without maintenance.
  • Windows that looks great. Our secondary double glazing systems are made in aluminium and finished in white polyester powder-coating as standard or we can powder coated them to your request. The attractive designs will improve the look and value of your home.
  • Greater security. Feel safe with the strong aluminium secondary double glazing and locks we provide.
  • A better lifestyle. A warmer house, lower energy bills and less outside noise are just some of the benefits that come with our secondary double glazing systems.

As well as manufacturing the secondary units to the highest standard, we ensure our installation service follows suit.

When purchasing from us you can have full confidence. We are well established and highly regarded company. We plan on continuing what we do for as long as we can, so take comfort in our fully comprehensive 10 year guarantee.

We also offer a secondary double glazing replacement and repair service. Should any of your existing windows become damaged, misted or need tidying up then we are here to help.

Come to our show room at the Glass works, Skeoge industrial estate Derry City Northern Ireland and have a look at these in person or contact us today on 02871 357 444. 

Our slim-line aluminium secondary glazing is of the highest quality.

Matched with our experience in glazing we can accommodate and create a custom system to incorporate or  be complimenting many styles and different options for any project.

Benefits of  an APG aluminium frame:

  • Lightweight,
  • Strong and durable.
  • Slim profile.
  • Bendable for curved and arched secondary glazing.
  • Draught-proofing.


  • Bespoke made to measure.
  • Supply and install service, fast and efficient low impact installation process.
  • Profile flexibility, Face fit (odd leg or subframe) or reveal fix ( extended subframe options)
  • Colours- White, Silver,Brown,or RAL matching facility.

Noise reduction.

Distributive noise levels can be a real detriment to the enjoyment of your home or working environment. Installing effective secondary glazing can be a cost effective way to significantly reduce this external nuisance. In these Situations APG can specify enhanced acoustic glass or laminated glass of 6mm plus thickness as an effective insulating secondary glazing system.

Thermal Insulation and draft reduction.

Secondary glazing supplies and installed by APG. Can reduce heat loss from existing single pane glazing by up to 50%.
Double glazed secondary glazing- Heavy duty frame. The Ultimate in Thermal and Noise reduction, Contact us today.

Design Styles

We have the Design freedom to deliver a product which is accommodating to most building styles traditional to modern contemporary.

Frame mechanical options:

Vertical sliding secondary glazing frame.

  • Suitable for traditional sash windows
  • Optional spring balances available to support sliding sash in any position.
  • Three different frame finish options.
  • Optional tilt back facility.

Horizontal sliding secondary glazing frame.

  • Suitable for Casement and Ribbon windows.
  • Sliding track using nylon pads or optional roller wheels.

Hinged secondary glazing frame.

  • Compatible for both windows and doors.
  • Butt hinged or friction hinged.
  • Two optional frame finish available.
  • Used where maximum ventilation is desired or for fire escapes.

Fixed double glazing secondary glazing units.

  • Cost effective enhancement to bay windows characterized by a secondary glazing system.

Glass Options.

Clear float,Obscure, privacy, decorative,textured,safety/ security glass, toughened, laminate, thermal performance or Acoustic glass.

Highest Quality secondary glazing, lightweight, highly effective, with a range of option in specialist glass designed to enhance categories of acoustic, thermal or security performance.

For further information please Contact us today on 02871 357 444. -or-  E-mail us.

Our Showroom and Factory are Located at the Glass works, Skeoge industrial estate Derry City Northern Ireland, we have expanded and developed both our product ranges and glazing capabilities over the years and now offer our services to all areas of Ireland, the United kingdom and internationally.