Frequently asked questions

Below you can find a selection of frequently asked questions on our products and services. If, however, you have a technical question which is not answered below, please contact us - we will be happy to help.

How to buy VELFAC windows

Can I buy windows directly from VELFAC?

For single houses and domestic projects, our products are sold exclusively through distributors, who can offer a great local service. They also have local showrooms so you can discuss your project details with them whilst viewing the products on display.

Learn more about how to buy VELFAC windows

Where can I see VELFAC windows?

There are different ways to see VELFAC windows and doors.

  1. Distributors showrooms: Many of our distributors across the UK have local showrooms where you can view and operate our range of windows & doors. If you would like to find out where your nearest distributor is, and what you can see on display, please contact our domestic sales team

  2. Exhibitions: Every year we attend some of the largest Exhibitions for selfbuilders in the UK. See the calendar and request free tickets for those events.

  3. National Self Build & Renovation Centre (NSBRC), Swindon: Visit our permanent exhibition at the NSBRC

Product features and certifications

What sizes are available for VELFAC windows and doors?

All VELFAC windows and doors are made to measure. Unlike off-the-shelf or standard-sized windows, our windows are designed and manufactured to fit unique or unusual openings, which means that they can be made to virtually any size that is required.


The sizes of a made to measure window will depend on the specific requirements of your project.  For example, it be designed to fit an unusually shaped or curved wall, or to maximize the amount of natural light that enters a particular room. Custom size windows can also be used to create a striking visual statement, such as by using oversized glass panels or a particular combination of shapes.


To determine the appropriate size for your windows, it is important to work closely with a professional window distributor. They can help assess the unique requirements of your project, and provide guidance on the options available to you, based also on any constraints related to the design, materials, or installation process.

Does VELFAC manufacture curved, round or shaped windows?

Yes. You can specify VELFAC windows in many different shapes and sizes - round or shaped windows are not a problem.

How can VELFAC windows help to reduce perceived noise levels?

VELFAC offers a variety of noise reduction solutions. Double glazed units can be fitted with different types and thicknesses of glass with noise-reduction values ranging from Rw32 to Rw41.

In extreme conditions VELFAC can offer a 2+1 noise reduction window, using optimum glazing solutions a Rw value of 48 (one of the highest in the industry) can be achieved.

Information on the relevant noise reduction tests can be seen in the Tests section and more information can be found in the 2nd part of the VELFAC 200 System of our catalogue.

How can VELFAC windows be made 'child-proof'?

The VELFAC window system includes a number of safety features designed with children in mind: safety locks can be fitted either before or after installation; a lockable handle can be fitted, featuring either a push-button or key-operated locking system; and lockable restrictors can also be supplied - these allow windows to be securely locked in place when opened for ventilation, ensuring the gap remains too narrow to pose any danger.

What security features do VELFAC windows have?

VELFAC products are Part Q compliant and we offer a Secured by Design product range. SBD is a Police initiative which aims to encourage the building industry to adopt crime prevention measures in development design, therefore reducing the opportunity for crime and creating a safer, more secure environment.

VELFAC has a selection of windows that have achieved the required standard Pas 24 for Secured by Design.

What U-value can VELFAC windows and doors achieve?

The VELFAC composite system can achieve a U-value as low as 0,8 W/m²K for triple glazing. Thanks to the composite construction, and the slim frame design, choosing VELFAC energy-efficient windows, you’ll take advantage of sunlight and avoid excessive heat loss through the pane. This could save you up to 30 percent on your heating bills compared to traditional style windows. 

Contact VELFAC for more information on U-values

Operation and usage

How do I care for and maintain my VELFAC windows?

VELFAC window systems are easy to use and maintain. The windows need only regular cleaning to maintain their appearance - the powder-coated aluminium external frame will resist even the harshest weather conditions.

The best method of cleaning is by regular washing with a solution of lukewarm water and mild detergent. All surfaces should be cleaned using a soft cloth or sponge, and nothing harsher than natural bristle brushes.

To maintain the window's operation, all moving parts should be cleaned and lubricated with acid-free oil once a year. Friction stays should be adjusted and hardware inspected.

If you would like more detailed information on the care of individual window components, download Section 9 of our Specifier's Manual.

If in doubt, the VELFAC after sales service department is available to give advice and, if required, a service contract to ensure the windows installed have a long and trouble-free life.

What warranty is offered from VELFAC?

At VELFAC we take great pride in the quality and durability of our windows and doors.  A comprehensive product warranty of 12 years for windows and 5 years for entrance, sliding and hinged doors is available through Distributors of VELFAC products. This covers all aspects of the units including the frame, glass, handle mechanisms and seals.  For added peace of mind, if the supplying Distributor is no longer trading, VELFAC will honour the remainder of the warranty period for products supplied. 

See terms and conditions on our warranty.

Please note, fees may apply.

My window doesn’t operate properly, what should I do?

If the window cannot be easily operated, check for any obstructions on the outside or in between the moving aluminium sash and the fixed timber mainframe. Ensure that no debris is obstructing the slide motion of the moving arm.

If you are still experiencing problems, check that the outside of the window is hanging square. If it appears to be a problem, some adjustments can be made using guidance from our Installation Guide, or you can contact the VELFAC Customer Service team for assistance.

I have some condensation on my windows glass, what can I do?

Condensation on glass window panes is a natural phenomenon that cannot be completely avoided, no matter how well insulated your house or how efficient your windows are.

Condensation occurs when warm, moisture-laden air meets a cool surface such as glass – the change in temperature causes the moisture to condense onto that surface in the form of water droplets. Colder external temperatures during winter months combined with heated internal temperatures will result in larger amounts of condensation.

The link below explains how and why condensation occurs, and what you can do to control it: Condensation explanation

Someone tried to break into my house and damaged my window, what should I do?

If the window is operable after being damaged by forced entry or accident, it should be closed and secured. If the glass unit has been broken, any remains should be carefully removed taking all necessary safety precautions i.e. wearing protective clothing such as gloves, safety glasses, suitable footwear etc.

When you contact the Police to report a suspected crime, ensure you seek advice on how to preserve the scene for forensic examination prior to clearing.

To restore building security, temporary glazing material (such as plywood or similar) may be fixed into the aluminium sash profile until a replacement glass unit is available.

How do I report an issue with a door or window once it has been installed?

  1. If you purchased the windows & doors after May 2021 through a VELFAC Distributor, you will need to contact your distributor. Your distributor or our customer care team will then contact you to discuss further actions.

  2. If you purchased the windows & doors before May 2021through VELFAC Direct, or moved into a property with VELFAC windows already installed, please complete an after sales request here.

Can I order replacement parts myself?

To order replacement parts, please fill the form available and advice which parts you require. If possible including pictures of the parts and of the unit unique identity tag

Following the request, VELFAC will provide a quotation for the required parts.

Delivery and installation

Who do I have to contact to track/check the status of my delivery?

To check the status of your delivery you would need to contact your distributor. They will be happy to give you an update.

How will my order be packed/delivered?

For information about how the products will be packed and delivered, please contact your distributors who will be able to provide more details.

What if I want to install the windows myself?

VELFAC windows and doors can be purchased on a supply only basis through one of our distributors. If you want to install your VELFAC windows and doors yourself, you can find guidance and installation details on our technical database

Is VELFAC FENSA certified?

FENSA stands for the Fenestration Self-Assessment Scheme. A FENSA certificate is your assurance that the installer who fitted your windows or doors has complied with Building Regulations.

FENSA certifications is therefore not applicable to the windows and doors, but can be asked to the distributor who carried out the installation, or obtained from your local building control authority.