Building Regulations for Windows & Doors in the UK

When replacing or installing windows and doors, it's important to understand the UK Building Regulations that may apply to your project.

Windows Trade Plus has simplified the key regulations relevant to windows, doors and glazing to help you understand the main requirements. For complete and up-to-date technical guidance, always refer to the relevant government regulations or contact our team for assistance.

• Part A: Structure
• Part B: Fire safety
• Part F: Ventilation
• Part I: Conservation of fuel and power
• Part M: Ease of access of disabled visitors
• Part N: Safety glazing until 6th April 2013 (removed, integrated into part K)
• Part Q: Security of New Build residence
• FENSA

For further technical information, please contact Windows Trade Plus or refer to the relevant UK Government Building Regulations guidance.

Windows Trade Plus has decided to index the building regulations in the most likely order of relevance of your project, and not alphabetically.

Windows Trade Plus is a bespoke manufacturing website. A FENSA certificate cannot be issued as this is a supply only service. For more information regards to FENSA certification please visit www.fensa.org.uk

If you have any question in regards to FENSA please contact Windows Trade Plus for more guidance.

Windows Trade Plus uses part N as the example for part K, as it is more relevant to windows and doors.

Toughened or laminated glazing is required in critical locations which are subject to accidental human impact. As a minimum:

• Glazing at low levels, the level of the glazing is within 800mm of the floor level to the glass line.
• Glazing in doors that starts lower then 1500mm from the floor level to the glass line.
• Glazing adjacent to door: window/side panels starting within 300mm of the edge of the door frame and also starting within 1500mm from the floor level, please see our simple diagram below. If you have any question please contact us.

The diagram shows the glass panes where toughened or laminated safety glass is required is highlighted in orange.

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

All rooms must be adequately ventilated to avoid the accumulation of contaminants and / or condensation, purge ventilation (direct fan) is required in rooms prone to water vapour such as bathrooms and kitchen. Water vapour can also be caused with items such as fish tanks. If the original windows have trickle vents, any replacement windows are also required to have trickle vents.

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

Fire escape windows must be provided with an unobstructed area of at least 0.33mm2 with minimum dimension of 450mm in height or width, and should not be above 1100mm from the floor. This is applicable to all second floor habitual rooms, not bathrooms, and lower floor if no direct means of escape in two directions, and garage extensions. This is clearly shown to be achieved on Windows Trade Plus website via an F highlighted in the glazing area. In some cases, this is not achievable and a-like-for-like design will be acceptable. In this instance Windows Trade Plus advises to take photos of the items being removed, in case an independant inspector requests evidence you have not made the design worse when replacing.

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

Accessibility is at the forefront of building regulations and are relative to the accessibility not only for disabled people, those with limited mobility and wheel chair users, but are also very useful for people that regularly use prams and other wheeled devices. There are three main areas to consider:

• M4(1) Category 1 - Visitable dwellings (the mandatory regulatory minimum requirements for all new dwellings) - considered to be met when any new dwelling makes reasonable provision for most people, including wheelchair users, to enter the building and enter and rooms and sanitary facilities on the entrance floor.
• M4(2) Category 2 - Accessible and adaptable dwellings (optional requirement depending on planning policy / developer choice) - considered to be met when a new dwelling meets reasonable provision for most people to access it, PLUS incorporates features making it suitable for a wide range of people, including older people, individuals with reduced mobility and some wheelchair users.
• M4(3) Category 3 - Wheelchair user dwelling (optional requirement depending on planning / developer discretion) - met when the dwelling makes reasonable provision for wheelchair users to live in the dwelling and make use of any parking facilities and outdoor or communal spaces.

For all new build developments, achieving Category 1 standards is mandatory, whereas, as stated above, the requirement to meet Category 2 and 3 will differ depending on the planning policies in the area you're building in. The local planning authority will determine the standard of accessibility required as part of the planning permission.

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

What this means is that when replacing windows and doors the item in not load bearing. In the 1930s - 1960s, wooden/steel windows and doors were built-in and used to build above. Now your products are changing, a modern window is not classed as a structural element, and it is the responsibility of the installer to make sure that all structural elements are taken into account.

Signs of movement are broken glass in the original windows and/or doors, cracks in the original frame, and movement in the brickwork in a pyramid form above or below the window and/or doors. Sometimes you are unable to determine if the original building has been built correctly as the building was constructed, great care is required when taking the windows and/or doors out.

Load bearing bays; a stone bay is generally load bearing by nature of the stone structure which means the windows are not load bearing. If the bay window is not a stone bay and has a roof which is not part of the main house, or an Apex roof, this is a clear sign the windows are load bearing. If the bay window goes across multiple floors with a barrel section in-between then this a clear indication the window sections will be load bearing. Windows Trade Plus supply load bearing poles with all of the bay purchases and bay jacks as an additional option which can be fitted to comply with document A.

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

Conservation and fuel power is a compulsory area. All windows and door that are replaced in habitable areas are required to have a rating of 1.6 U value or lower. A simple system to calculate these are the WERS rating, or more commonly known as energy efficiently rating BFRC. Like you see on your washing machine, Windows Trade Plus offers B rated windows, but the more commonly produced windows produced are A rated windows. There is a section to be able to order none rated windows but these are for out buildings only with no heating, i.e a shed, Windows Trade Plus is able to offer A++ windows but these are not common as the temperatures with in the UK very rarely required require such a high specification and there are certain parameters that change the style / specification of the windows. You will also need to contact us to obtain a quote.

Extensions: it is recommended that the maximum area of glazing relative to a build is 25% or lower. If the glazing area is less than 25% then the standard rules apply. If the area is higher than 25% then there will be information on the architects drawing to comply by.

Some sorts of building are exempt from building regulations. These are listed buildings and those within conservation areas. Were these buildings to be modified, they would lose some of their character. With that said, these sorts of buildings can often be fitted with newer, energy efficient doors and windows without compromising their aesthetics.

Another important category of allowed developments are conservatories and porches, provided that the development in question doesn't have a heating system and is less than 30m².

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.

Part Q is only relevant to new build properties. Its aim is to prevent people breaking into others homes through lower level doors and windows. In regards to flats any part which there is access to the flats.

This is mainly the ground floor windows and other easily accessible windows, door sets should be of a PAS 24.

One of the main aspects missed for this regulation is the windows and doors will require laminated glass in all sections. Windows Trade Plus would also recommend a composite door.

Another important category of allowed developments are conservatories and porches, provided that the development in question doesn't have a heating system and is less than 30m².

For more information visit the government website here or please contact the Windows Trade Plus technical department, technical@windowstradeplus.co.uk for more guidance, or telephone 02476 100750.