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Call the hotline on: 0845 300 2927

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Frequently asked questions

What does this mean to you?

It means that if you manufacture replacement windows, you must be able to prove to Building control that the windows you have built achieve a whole window value of 1.6 W/m2K and therefore comply with Part L of the Building regs.

Why do I need to conform to Part L of the Building Regs 2010?

Building control will be responsible for checking. They must be informed of all replacement window installations regardless of whether they are installed by a company or as a DIY project.

When did this come into force?

1st October 2010.

What do I have to prove?

You have to prove that windows you manufacture achieve a minimum whole window U-value of 1.6 W/m2K.

How do I prove this?

You will need to show that the window design has achieved the required standard. This has to be done by either computer simulation or a 'Hot-box' test, and an Air Permeability test on an actual sample of the window(s).

Do I need a BFRC Energy rating?

No you don't, you just have to prove a whole window value of 1.6 W/m2K. However, if want your windows to carry an Energy rating label, you can in addition choose to go through the process of assessment for the awarding of a BFRC Energy rating. This is not compulsory, but if you wish to pursue this, we will guide you through the process. Our windows achieve a C rating (1.6W/m2K) and a B rating (1.4W/m2K)

How much will this cost me to put in place?

If you choose to use a Mighton window system, THERE IS NO COST as we will supply all the drawings, documentation and assistance you need. If you go it alone, it can cost in excess of £4,100 to get one window designed, tested and approved.

What is so different about your window systems?

Our 3 window systems are fundamentally the same as the windows you have produced in the past (at the same cost), except we have had them tested with our weather-stripping and hardware to prove that they comply with the new regulations.

What types of window do your systems cover?

EcoSash™ is a traditional Weights & Pulleys window
EcoSlide™ is a traditional Spiral Balanced window
EcoSafe™ is a traditional Tilt & Slide window

What else do I need?

You will need to keep a record of the window system that you have produced, together with a record of glass and hardware supplied and be able to prove you conformed to our design.

What do I do next?

Call us now on 0845 300 2927 and register your interest and we will supply you with our drawings, test results and a simple document for recording your projects.

What about listed buildings?

Listed buildings, buildings in conservation areas and scheduled ancient monuments are exempt where compliance would unacceptably alter the character or appearance of the buildings.