Chairman John Barnett formed AGS in 2001 with his son Andrew Barnett and wife Julie Barnett. All three had been in the industry for many years and all three had become increasingly disillusioned with their previous employer’s reluctance to provide complete customer satisfaction.


Here at AGS, our aims are simple; provide the public with high specification windows, doors, and conservatories at affordable prices. From the point of sale, through to the completion of an installation, every department will be dedicated to fulfilling its obligations professionally, efficiently, and quickly.

This code of practice guarantees our customers that the otherwise anxious experience of such a large purchase will be a happy one. It doesn’t end there though... After all, you have our comprehensive 10-year warranty to give you peace of mind. That’s why it is imperative that AGS only employ people who share our views and have pride in their work.


The quality of our products and services is taken very seriously at AGS. We understand that if we provide you with a top quality product and install it professionally, using proven methods, not only will we avoid future problems, but you will also be happy to recommend us to your family and friends. It is our belief in these principles that has resulted in AGS obtaining a 100% customer satisfaction level in a recent Installation Quality Survey by trustatrader.com.

Remember, always look out for the British Standard Kitemarks, Energy ‘A’ Rated Windows and the Glazing Ombudsman as a sign of quality.


Rest safe in the knowledge that the comprehensive ‘no quibble’ 10 year warranty from AGS can be backed up with a matching insurance-backed policy from GGFi. This ensures that your investment is protected even if we amalgamated with another company.


One of the main distinctions between AGS and our competitors is our superior range of modern products.

It is important that customers understand we source not only the best frames and glass, but small, otherwise forgotten elements such as neoprene gaskets and zinc alloy locks. Only the best furniture and hardware is used when manufacturing your projects.

All glazing products use Pilkington’s most advanced 28mm double-glazed sealed unit, comprising two panes of thermal glass, Argon gas filling and Swiss V Warm Edge space bar, achieving a window energy rating of ‘A’.

All glass conforms to British Standard BS5713 & BS6206. All PVCu products are manufactured using grade 1 profile conforming to BS7412 and manufactured under BS7413. Welded dividing bars are used for additional strength and are fully reinforced with galvanized steel, to British Standards.

You can feel safe in the knowledge that our locks adhere to the most stringent industry and insurance requirements, conforming to British Standard BS7590 (PAS011).


We Believe In....

  • That customers should get Value for Money
  • In the Best Installations for our customers
  • In a first rate Customer Service
  • That queries should be Resolved Quickly
  • That Customers Come First... always.

Don't forget....

For every recommendation that we receive, with a value of £1000 or more, we will pay £50 directly to you - simply for telling the truth!