Legal requirements for installing windows: what you need to know

Key Highlights

• Understanding the rules and regulations for installing windows in your home is essential to make sure your project goes off without a hitch
• UK building regulations and seeking planning permission for replacement windows are two different things worth noting before beginning your home improvement project
• A window’s U-value and thermal performance shouldn’t be overlooked to prevent unwanted heat loss and to reduce monthly energy bills
• Timber windows make a fantastic replacement with their incredible aesthetic and modern performance
• Work with a window supplier which goes the extra mile to benefit from unrivalled advice and support throughout the entire process

Thinking about updating your home with beautiful new windows?  Whether you’re replacing tired old frames or adding windows to a new build, it’s important to be aware of the legal requirements in the UK. Here at Bereco, we’re passionate about supporting homeowners to ensure they find beautifully bespoke timber windows for their property, while ensuring everything complies with the latest regulations.

In this blog, we’ll guide you through the key legal considerations for window installation so you can complete your home renovation project with confidence.

Understanding building regulations

Building regulations in England are a set of rules designed to ensure the safety, energy efficiency and accessibility of buildings across the country. When it comes to windows, several parts of the new building regulations are relevant and, while it’s the responsibility of the window supplier to make sure all replacement windows are compliant, they are worth noting:

Part B (fire safety)

This specific part of the regulation focuses on means of escape in case of fire. New and replacement windows in habitable rooms (bedrooms, living rooms) on the ground floor and upper floors of up to 4.5 meters from ground level must be able to open and provide a clear opening of at least 0.33 square meters, with a minimum dimension of 450mm width or height.

Part L (conservation of fuel and power)

This part relates to energy efficiency and was introduced to the UK in June 2022. Approved document L states that all new windows must have a notional U-value (how a window’s thermal performance is measured) target of no more than 1.2W/m²K and a Window Energy Rating (WER) of B or better.

Please note: it is possible to use the limiting standard of 1.4W/m²K but this will affect other parts of the SAP calculations so it’s always worth exploring this in detail.

When it comes to replacement windows, they must have a U-value no higher than 1.4W/m²K and a WER of B or better.

Part F (ventilation)

Part F or approved document F is an additional part of the legislation that focuses on ventilation within homes and ensures indoor air quality is maintained in buildings.

Building work and planning permission

Not all window replacements require planning permission. However, if you’re working on larger projects or alterations that affect the external appearance of your home, you might need to apply for planning permission.

If you’re unsure whether this applies to you, it’s always best to check with your local authority building control team to be on the safe side.

Thermal performance and U-values explained

How well a window retains heat within a home is incredibly important. U-values are a specific industry measurement designed to demonstrate whether any heat is lost through a window.

In terms of what the figures mean, the general rule of thumb is that the smaller the number, the better that window is at retaining heat. Therefore, it successfully keeps your house warm, saves energy and reduces the amount of carbon emissions produced.

By selecting new windows with good U-values, you may also notice a difference in your heating bills as it takes less energy to warm your home. Plus, you’ll be benefit from a more comfortable and warmer indoor environment during the winter.

Ultimately, if you’re on the hunt for replacement windows, always consider their thermal performance as well as how great they look aesthetically.

Certificates of compliance and their importance

Certificates of compliance, like a FENSA certificate, will help you to identify if the replacement windows you invest in meet the UK building regulations. Awarded by a third-party organisation means that any window supplier with these certificates can confidently say they are assessed regularly to ensure they remain compliant with the regulations.

Why timber is the perfect choice for meeting legal requirements

At Bereco, we specialise in crafting beautifully bespoke timber windows which effortlessly meet the necessary legal requirements and here’s how:

Energy efficiency

Modern timber windows, like those we supply at Bereco, are designed to deliver exceptional thermal performance. In fact, our windows achieve U-values well below those listed in the building regulations thanks to double glazing, triple glazing and advanced insulation.

Durability and safety

High-quality timber windows are incredibly strong and can withstand the harshest weather conditions, which means they last for many years. The glass used in Bereco windows also meets the fire safety requirements under Part B, meaning homes are well protected in the event of fire.

Beyond UK regulations: the Bereco difference

While complying with legal requirements is essential at Bereco, we also believe in going the extra mile which is why we work tirelessly to supply premium timber windows to our customers across the UK. Here are some examples of what sets us apart as a wooden window supplier:

Truly bespoke

We offer a wide range of styles of timber windows including flush casement, lipped casement, sliding sash and tilt & turn windows. No matter which style you choose, each window can be completely customised. This includes everything from the type of bar designs selected to the ironmongery and paint and stain finishes.

With the ability to pick the design and style of your timber windows, you can find a solution that perfectly complements your home’s character.

Sustainable sourcing

As a window supplier who puts sustainability at the heart of what we do, we source our timber responsibly so that you can feel confident the replacement windows you’re investing in are an environmentally friendly product.

Exceptional service

Our friendly and professional team, made up of customer service specialists and experienced installers, are here to guide you through every part of the process right from the initial design consultation to providing after care support and advice.

Conservation areas and listed buildings

Installing new windows into a property located within a conservation area requires more thought because the architecture and heritage of the building must be protected. Any changes to the dwelling should maintain certain historic qualities while delivering modern thermal performance.

If you live in a conservation area or want to check if your property is classed as a listed building, speak to someone within your local authority for advice. The team should be able to advise you on what can and can’t be done regarding window styles, materials and finishes in these areas. They’ll also highlight if you need to get specific permissions before making a start on your home improvement project.

Ready to explore high-quality, compliant windows?

Contact our team today. We’ll be happy to discuss your project in detail and help you find the perfect timber window design and style for your home.

Please note: This blog is a guide only and all homeowners must take responsibility for thoroughly reading the building regulations to ensure any new or replacement windows are compliant. We cannot be held responsible for any errors regarding the legal requirements of window installations.

Frequently Asked Questions

Do I always need planning permission to replace windows?

You don’t usually need planning permission to replace the windows in your home unless your property is classed as a listed building or is located within a conservation area.

Always double check with your local authority to make sure your window replacement project runs smoothly.

Can I install double glazing in a conservation area?

It’s a good idea to talk with your local authority to check what the rules are where you live and help ensure everything is done correctly.

What are the penalties for non-compliance with building regulations?

Non-compliance with building regulations can be a costly error so make sure all building work, like installing windows, follows the rules.