How to Comply

Door installer


The changes to Part L of the Building Regs came info force on 15th June 2022. With lots of mixed messages across our industry, it can be difficult for fabricators and installers to be sure which compliance route best suits their business.

Should you switch existing systems to triple glazing and incur the costs and handling issue? Should you follow U-Values or WER/DSERs?

With the Future Homes Standard ahead of us, AluK has taken a proactive approach to ensure our products comply now and require only double-glazing. This will help reduce the environmental impact of our products without imposing the higher costs of using triple glazing.

Our approach has been to upgrade the thermal performance of our existing products so that they comply with the notional or limiting values set out.

Optio 58BW Casement

How do AluK products comply?

As a systems house, we have no choice but to comply with the new lower U-Values. We support the aim to reduce our carbon footprint in the UK and want to play our part by ensuring our windows and doors meet the new Notional values.

It’s also important to us that we support our fabricators and you, the installer, by ensuring we meet these lower U-Values with the same products and using double glazing.

Why is this important?

  1. The glazing market is not geared up to provide triple-glazing in volume.
  2. The cost of triple glazing is not competitive.
  3. Many fabricators are not able to manufacture triple glazed systems at volume.
  4. The weight of triple glazing makes it more difficult to handle and install, whilst putting more pressure on hinges and hardware.

How have we changed
our products?

Our route to meet the new regulations and support our customers has meant engineering many improvements to the internal design without changing the appearance of our systems.

Using new thermal break designs and foams, and new gaskets, our well-loved products have been modified to comfortably meet the new regulations for new build and existing dwellings.

Green House
Green house products

Why Should I Comply?

The policing of the changes will be regulated by the local authority Building Control Bodies. It has been suggested that Building Control will manage the policing by:

  • Employing additional resource. It has been implied that circa 1,100 new Control Officers will be employed
  • Larger fabricators will be initially targeted
  • Postcode areas will be selected at random and heavily monitored Failure to comply may result in:
    • Prosecution in a Magistrate’s Court where an unlimited fine may be imposed. This action is usually taken against the person carrying out the work (builder, installer or main contractor)
    • Alternatively, or in addition, the local authority may serve an enforcement notice on the building owner requiring the alterations or removal of the works. If the owner does not comply with the notice the local authority has the power to undertake the work itself and recover the costs from the owner.

Are you an installer?

Where does installation sit

within Approved Doc L?

Windows and doors installed into a New Build are required to be sealed with air sealing tape around the structural openings. Compressible seals or gun sealant may be used to supplement taping. Photographic evidence may be required for sign off.

Installation tolerances are to be in accordance with BS 8213-4 – Windows and Doors – Part 4: Code of practice for the survey and installation of windows and external doorsets.

Windows or Doors should be located with an overlap between the inner face of the unit and the inner face of the external leaf – for windows an overlap between 30-50mm and for doors 50mm – so that the window or door unit in contiguous with the insulation layer of the external wall.

Fully insulated and continuous cavity closer should be used, installed tight to the insulation and cavity apertures. For door units, install perimeter insulation within the threshold zone or use reinforced cavity closer.

Download our Free Installer Doc L Guide


or contact us to request a printed copy:

Installer Guide Diagram


If you’d like more information on the Future Homes Standard, changes to Part L and AluK’s Part L-ready products, please get in touch with your local Area Sales Manager.

  • Rest assured that AluK products are fully compliant and we’re clear about which products are suitable for new build projects and existing home.
  • Products designed based around area of sales. Eg. New Build, Existing Dwellings etc..
  • Technical Services team available

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The AluK HQ reception in Cheptow