FENSA certificate

FENSA is a name you may have heard but you might wonder, what does FENSA stand for? It is an acronym for Fenestration Self-Assessment Scheme. It was set up, with approval from government bodies, by the Glass and Glazing Federation (GGF).

The organisation’s primary function is to regulate double glazing companies and ensure compliance with Building Regulations, with approved industry bodies receiving certification and then, in turn, being able to award homeowners with a FENSA certificate when their installation is complete.

If you want to replace double glazing, it needs to comply with the Building Regulations for thermal performance. Now, you could choose to go and get the necessary permission and certification for this from your local building authorities yourself. Alternatively, you can get an accredited installer to provide you with FENSA windows that will be certified, so they can do much of the hard work for you.

A FENSA-registered double glazing installer will be aware of local building regulations. Moreover, they will be equipped under the Competent Person Scheme to certify the installation of your new FENSA windows. As a result, you don’t have to get the approval and certification yourself. You can hand over the responsibility to your installers. They will take care of everything from start to finish.

What is the Competent Person Scheme?

The short answer is, this is a form of self-governance and regulation. These government-approved bodies register installers. They do so after making sure that their service and installation is up to the mark. Once they are registered, they are given the authority to self-assess and certify their installations.

In April 2002, the government decided to regulate double glazing installation. However, it is quite a task to manage, monitor and certify all windows and doors installations across the country. This is why the Competent Person Scheme was created.

There are 6 bodies that were set up under this scheme. Each of them monitors its members. Additionally, each of them equips its members to certify their installation. Since the regulatory bodies manage their own members, it’s a self-governed process.

This makes it easy for building authorities to ensure compliance. Moreover, homeowners don’t have to run around to get paperwork and certifications for their new double glazing.

FENSA approved installers make planning permissions and certification easy

What is the Purpose of FENSA?

FENSA was established due to the change in regulations in April 2002. This is when Building Regulations decided that double glazing installation needed to be standardised. This was necessary to lower the national carbon footprint.

When we heat up our homes, a certain amount of heat escapes through conduction. The biggest culprits are the doors and windows. Single glazed windows and doors are notorious for not retaining heat inside.

The more heat your doors and windows let out, the longer you have to run your heating. As a result, your home consumes more power. If you could insulate your home better, you would not need as much energy in heating.

By regulating the thermal performance of double glazing, FENSA and GGF are trying to reduce energy consumption. Additionally, these bodies also ensure that regulations for ventilation and fire safety are followed too.

How Does FENSA Function?

The way FENSA works is by inviting double glazing companies to register. They then screen each applicant for their quality and performance. After they are satisfied that the applicant is up to the standards set by them, they allow them to display the FENSA logo.

Additionally, the installers get an ID that displays their company along with their FENSA affiliation. Once FENSA registers the company, they can assess their own installation. When they complete the installation, they can issue a FENSA certificate of compliance.

In order to join the FENSA network, companies have to prove their commitment to quality. To this end, they need to do more for their clients. As a result, you get an insurance-backed guarantee on your installation. They are also required to provide deposit protection to their clients.

Why Should You Choose FENSA Approved Installers?

FENSA approved installers give quality service and installation

Even though there are 5 other Competent Person Schemes that regulate double glazing installations, FENSA is the most popular. This is because of its high standards and commitment to excellence. As a result, it also has the largest network of approved double glazing companies.

When you choose FENSA windows from an approved installer, you get the benefit of this body’s standards and protection. You can be sure that your installation will be of the highest industry standards. Moreover, the body protects the customer’s interests with compulsory guarantees and indemnities. The FENSA certificate awarded at the completion of the installation will give you complete peace of mind about the quality of the work.


You can find FENSA-registered double glazing companies extremely easily. You will be able to find many recommended local companies on their website.

Additionally, they provide all accredited installers with a member ID card. The card displays the installer’s name and company, as well as the FENSA logo. This card’s security features are designed in such a way to make the card impossible to fake, so you are guaranteed exceptional workmanship as promised.

This regulatory body demands high standards from all its members. FENSA constantly monitors and re-assesses to strive for ongoing perfection. As a result, you have the peace of mind and the assurance of a regulatory body.

Double glazing repairs can be costly. That’s why FENSA windows from an approved installer are the best choice, as they will be fitted to the highest standards initially and covered by a guarantee in the unlikely event of a problem.


As per the requirements of FENSA, all registered double glazing companies need to provide insurance for their work. This includes the installation quality as well as certain aspects of the performance.

Moreover, an indemnity protects your initial deposit. Essentially, FENSA protects your double glazing and you. When you choose FENSA windows, you know you will be choosing the best.

Compliance and Certification

One of the biggest headaches you might face with new double glazing is getting it certified and registered. Suppose you call an unapproved installer to install it. Now you run the risk of it not being compliant with regulations. In such a case, your installation will not be certified. Additionally, the installer and you may face penalties.

With FENSA approved installers, you don’t have to worry about such problems. They ensure that the installation complies with building regulations. Moreover, they can certify their own installation, so you won’t have to waste your time getting the certification from local authorities. You will receive a FENSA certificate to mark the completion of the job and the high standards to which it has been completed.

Moreover, they will also get your double glazing registered. The best part is, the installation price covers all these aspects of the service, so you will reap the benefits of these additional features without any extra costs. This way, you will save time and money as you enjoy the convenience of not having to deal with any unnecessary paperwork!

Find a FENSA Approved Installer Near You

If you are looking for a reliable double installation, we are happy to recommend a FENSA registered company near you. Simply get in touch with us. Someone from our team will contact you and give you a list of registered local installers.

Alternatively, you can use our online quote generator to get a quick quote. Once you’ve informed it of what you need, it will generate a personalised cost instantly. Additionally, you will receive a list of local installers as well.

Frequently Asked Double Glazing Questions

Frequently Asked Double Glazing Questions

Can Double Glazed Doors be Fitted with a Pet Flap?

Depending on the style of door, a pet flap can be fitted as an extra service. The only exception is when glass panels feature on the lower half of the door.

How Much Do Doors Cost?

Your double glazed door cost will depend on specifications such as style, size, locks, glazing and door furniture. Double Glazing on The Web gives you the opportunity to create your very own unique door quote online. Start your free door quote today.

What Does UPVC Stand For?

UPVC is an abbreviation for unplasticised polyvinyl chloride which is used in window frames.

Do UPVC Windows Need Trickle Vents?

Trickle vents are not a requirement, however they do offer additional ventilation without the need for opening your windows so can be a valued add on.

How Long Will It Take To Install My Casement Window?

Because every job is different, it is best your talk to your double glazing installer who will be able to give you an exact timescale.

Which Bi-folding Door Configuration is Best?

When choosing the arrangement of your bi-folding doors you need to consider the size and layout of your room. Outfolding bi-fold doors will take up less internal space when completely folded back and a left of right folding will be dependent on space available in your room.

How Long Does It Take To Install Bi-Fold Doors?

If a survey is scheduled within 48hrs then your bi-fold doors can be supplied and installed within just 6 – 8 weeks.

How Secure Are Bi-Folding Doors?

Bi-folding doors are extremely secure and are built with a high security locks as standard. Each of our double glazing installers will offer their own range of locking systems with additional upgrade options for all security conscious homeowners.

Are There Other UPVC Casement Window Styles?

Other UPVC casement window styles include the French casement window which is a more traditional take on the standard casement style.

Will I Have A Choice of Casement Window Locks?

A high security lock will be fitted as standard with your new casement window but your double glazing installer will also offer a choice of security upgrades.

What Are Flush Casement Windows?

Flush casement windows are where the unit sits flush to the frame, creating a super sleek look.

Are There Different UPVC Casement Window Sizes?

UPVC casement windows come in a wide range of sizes to suit your property. You can specify your casement window size in our window cost calculator to get a unique window price!

Can I Choose My Casement Window Handles?

Your double glazing installer will offer you a choice casement window handles and casement window hardware options so you can achieve the perfect look.

What is a Casement Window?

A casement window is attached to its frame by one or more hinges. A casement window is hinged at the side allowing them to open extremely wide. These windows can double up as emergency exits and are perfect for hard to reach places within the home, with many home owners installing these windows behind their kitchen sinks.

Where Can I Get A Tilt and Turn Windows Price?

You can get a tilt and turn windows price using our window cost calculator which will give you a free and unique quote within a matter of minutes.

How Does The Tilt and Turn Window Mechanism Work?

The tilt and turn window can be ‘tilted’ inwards due to its unique turning action which allows the window to be easily accessed from both inside and out. All it takes is a swift turn of the handle.

How Much Do French casement windows cost?

The cost of French casement windows will vary depending on installer but you can get an average casement windows cost using our free online quoting engine

How do UPVC Sash Windows Work?

UPVC vertical sliding sash windows are built to either slide vertically downwards or upwards. This opening function makes the UPVC sash window much easier to use compared to traditional wooden windows where the only choice is double hung and single hand.

Are UPVC Sash Windows Easy To Use?

UPVC sash windows are very easy to use. Their spiral balance mechanism allows for smooth operation so you can open and close your windows with ease. UPVC sash windows are also incredibly low maintenance and require very little cleaning.

Why Should I Choose a UPVC Sash Window?

UPVC sash windows are incredibly attractive and make a stunning addition to any property and are relatively low maintenance thank to their UPVC design. You can enjoy a traditional aesthetic for many years to come thanks to their long standing properties.

Replacement Sash Windows In A Conservation Area

If your home is a listed property or within a conservation area then you will need to seek planning permission.

Are UPVC Doors Easy To Maintain?

UPVC doors are extremely easy to maintain and will never require re-painting or varnishing. Neither will a UPVC door rot or warp!

What Are Composite Doors Made Of?

Composite doors are made of a combination of high performing materials which is why they are so strong and incredibly long lasting. The composite door is made from: reinforced UPVC, fibreglass skin, high density foam and a water resistant composite materials.

Do Composite Doors Fade?

Composite doors feature a tough and durable skin where colour runs throughout rather than a simple surface coating. This means a composite door is not likely to wear or fade like the majority of painted doors. A composite door is very long lasting which also reduces the amount of maintenance required to keep it looking in top condition.

Do Composite Doors Need Painting?

Composite doors do not require re-painting. These low maintenance doors feature a water resistant GRP, coloured skin which keeps a pristine appearance year after year.

Do Composite Doors Warp?

A composite door will not warp like wood and won't require regular painting.

Can I Get Composite Side Panels?

Composite doors are available with matching composite side panels, your installer will offer you a choice of colours and glazing.

Is Every Composite Door Different?

There are different qualities to every composite door and they will vary between manufacturers depending on materials used. At Double Glazing on The Web we only put you in touch with the highest quality suppliers and installers.

What Do Stable Doors Look Like?

These country style doors offer charming aesthetics and are a stylish alternative to standard back doors, stable doors a great choice for any kind of property. This door is split in two halves which open independently from one another as well as function as a whole. Whether you are after a traditional stable door or more contemporary design with modern glazing, your double glazing installer will be able to offer you a wide range of options for your property.

Are UPVC Stable Doors Made To Measure?

Your UPVC stable door will be made to measure and tailored to your specifications given to your double glazing installer.

How Much Do UPVC French Doors Cost?

UPVC French door prices will depend on your personal requirements and specifications such as size, style and glazing. To get an average French doors cost use our door cost calculator for a free online quote.

Are UPVC Patio Doors Secure?

UPVC patio doors can be fitted with a choice of high security locks to make them extra secure. You can also choose from a range of glazing styles to further enhance the strength of your patio doors.

Do I Need Planning Permission For Patio Doors?

You may require planning permission for double glazed patio doors if you have a listed building or happen to live within a conservation area. Visit the V for more information.

How Do Sliding Patio Doors Work?

UPVC sliding doors operate on a smooth, easy glide system which allows for effortless transition. They are attached to metal or vinyl tracks which are fitted to the top and bottom frames and plastic rollers are added to ease the movement.

How Do Slide and Swing Doors Operate?

A multi-pane door with individual panes slides on a single track with no loss of space. Panes are able to operate individually with no visible hinges or hardware. The slide and swing door can open up spaces between rooms or between home and garden or even conservatory.

Bay or Bow Window?

Simply put, it really depends! Bay windows offer often much welcome and useful extra storage space to the frontage of homes. On the other hand, bow windows provide a curved shape alternative in terms of look compared to bay windows. They are both beautiful options and can add much character and charm to the right property.

Can Bay Windows Look Modern?

Bay windows can easily be either modern or traditional depending on the combination of glass and / or coloured uPVC profiles now available. Subsequently, its easy for these windows to seamlessly blend in with contemporary or old properties.

Can Double Glazed Windows Reduce My Heating Bills?

When you install double glazing in your home or commercial property, it is likely that the extra heat retention will lessen the need to use central heating systems. In turn, this could mean you see a drop in heating bills. If you are concerned about your energy bills, it is easy to compare business energy or home energy online.

What Makes Flush Sash Windows Different?

Flush sash casement windows are specifically designed to imitate the appearance of traditional wooden timber windows by appearing to have the same sashes that finish 'flush' with the outside face of the window.

Should I replace my old sash windows?

Sash windows are a key feature for many traditional period buildings. Sash windows were traditionally built using timber, which is fairly high maintenance and has a tendency toward rotting and warping. Over time, these windows can become draughty and insecure. uPVC sash windows are a great way to experience the benefits of modern double glazing, without sacrificing the aesthetic of your home. uPVC sash windows will not rot or warp and require little maintenance. They are also thermally efficient, which means that your home will not require as much heating.

How much does sash window restoration cost?

The cost of sash window restoration will depend on the survey result. Standard draught proofed sash windows (without sill replacement) usually starts at about £500 per window. The time taken will also depend on the survey result.

Can I install double glazing into my original sash windows?

This will depend upon what type of window you have. Replacing existing moving sashes with new, double glazed replicas might to be possible.

How much does it cost to replace a sash window?

The cost of replacing a sash window will depend on many factors including: style, size, material and glazing. A wooden sash window will cost significantly more than a uPVC sash window. A wooden sash window can cost up to £1000. Wooden windows are more expensive to manufacture so expect to pay that bit more. uPVC sash windows can be designed to mimic wood and are much cheaper in price. The starting price for a standard uPVC sash window is on average £525.

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