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Triple glazed timber replacement windows for Manchester retrofit

An extensive house renovation in Manchester, to improve the comfort and energy efficiency of a 1950s red brick house with a 1990s extension, has recently been completed. Clients Alan and Monica were looking to transform the house into a warm and comfortable home and to reduce its energy consumption and carbon footprint.

The project involved the replacement of all windows and doors with 21°’s ULTRA triple glazed timber range, with a whole window U value of Uw 0.75 W/m2K.

Energy efficient renovation

Alan and Monica undertook considerable research before deciding what measures were needed for the project, including a survey from URBED and a Design Review with 21°’s Bill Butcher. After a lot of consideration they decided not to go for external or internal wall insulation or MVHR but undertook the following energy efficiency measures:

  • Replacement of windows and doors throughout
  • Timber floor replaced with an insulated concrete floor
  • Cavity walls filled (and internal wall with cavity filled)
  • Small porch extension and full insulation of porch
  • Upping insulation levels where possible
We wanted triple glazing because of the comfort benefits of triple glazing, removing the cold down draughts from the glazing. We knew 21° from previous positive customer experience and also through the Carbon Coop, which we had recently joined. We did extensive research and got prices from 15+ window and door companies and we found that there was nothing to touch 21° on quality or price. They are great products – beautiful triple glazed wooden windows and doors with top of the range thermal properties. We found the price to be highly competitive – the price was less than any comparable product in any material, and in some cases up to 50% less. Since we have moved back in we have found the windows and other energy efficiency measures have made a great difference to the overall comfort and warmth of the house through the winter.

Alan & Monica

In addition, other improvements were made to the house during the refurbishment:

  • Moving of main bedroom from front of house to back of house
  • Moving of ensuite from back of house to front of house
  • Refurbishment of three bathrooms
  • Complete rewire
  • Complete re-plumb
  • Complete re-plaster
During the whole of our major house refurbishment 21° was the best company we dealt with, and indeed probably the best company we have ever dealt with in our life. Their fitting service was great and we would highly recommend them. They turned up on time with everything; fitted the windows expertly; were very knowledgeable and friendly and nothing was too much trouble 21°’s customer service has been second to none. When we were designing the windows we changed our minds several times about window openings, sizes, colours etc etc. None of that was any trouble. The surveyor came out twice (without charge) to make sure everything was how we wanted it. 21° have also offered an excellent after sales service. One of the doors was sticking; and it was no problem someone was sent out to adjust it. We were then told that this policy lasted for 10 YEARS – if anything is wrong – we can get in touch. We have found that everyone – but everyone – at 21° is incredibly helpful and friendly.

Alan & Monica

Triple glazed timber windows & doors

The existing windows in the house were old and had been poorly maintained, with rotten frames and failed glazing. 21°’s ULTRA triple glazed timber entrance doors, outward opening casement windows and one large inward opening window, in RAL colour 6021 (external) and clear timber finish (internal), were chosen to replace them.

Project details



Case study


Life changing homes