Help & Info

We’re here to help, both potential buyers and our existing customers.

We hope that this page covers your query, but please do feel free to get in touch, should you have any questions not covered or we can help with any further advice.

Frequently Asked Questions

FAQ: Ordering Process

Yes, we hold a wide range of our most popular products at our Bridge Street Leatherhead showroom.

It is available by appointment between 9am and 5pm on week days- please contact us to arrange a suitable time to visit.

In the first instance, please contact us and let us have a brief overview of your requirements.

Once we are sure we are able to help, we will make an appointment to visit you in order to discuss your project in detail and to measure up.

We will then work on your quotation at our office and contact you as soon as we have an accurate quotation ready. At this point we will be able to give an estimate of how long it will likely be before we are able to install your windows or doors.

At this point it is up to you to decide whether to proceed with the project or not. If you do, we will take a deposit in order to proceed further as everything is made to measure, with the balance payable after your windows or doors have been installed. If not, no hard feelings!

We pride ourselves on no pressure sales and completely free quotations.

This will depend on the type of product(s) ordered, and the current manufacturing and fitting workload, but as a rule of thumb we try to have windows fitted within six weeks and composite front doors 8 weeks from the date that the deposit is paid.

FAQ: Certification and Warranty

Most windows and doors supplied by db Designs carry a 10 year manufacturer's warranty.

There are a couple of exceptions to this rule, we will be discuss this during our initial visit to your property so you are fully informed from the beginning.

All of our installations carry a legally binding Building Regulation Compliance Certificate provided by Certass, who provide a self-certified scheme. Following our installation, they will contact your local Local Authority Building Control Office and pass on the relevant details.

The title Certass comes from ‘Certification and Self Assessment’. Certass is a Limited company and has been a Government Authorised Certification body since 2006.
Certass allows glazing contractors to self-certify installations as an alternative to using Building Control. Certass offers an efficient Competent Persons Scheme that gives contractors better support for their business.

The Certass Process

Certass Certification Scheme membership requires contractors to follow a set process. The steps can be seen as follows:

  • Before work begins, contractors must provide a consumer Contract explaining the work to be undertaken.
  • After completion, Certass contractors must provide the domestic consumer with a written guarantee to cover the installation work. Certass contractors must also at this point provide an Insurance Backed Guarantee (IBG) to cover the Building Regulation requirements for 6 years should they cease trading.
  • db Designs will register installations with Certass.
  • At this point, where applicable for Building Regulation requirements, Certass will notify the Local Authority of the installation completed at the property address.
  • Certass then issues the legally required Building Regulation Compliance Certificate (BRCC) to the domestic consumer/homeowner as proof of compliance.
  • Certass also carry out on-the-spot audits on various Certass contractors to ensure the work has been carried out in-line with the required standards.

FAQ: After Sales Care

Condensation is typically caused by excess moisture within your property. This can be more evident following new windows or doors due to the greater air-tightness that they provide.

Moisture in your property can come from any of the following sources:

  • Breathing
  • Boiling a kettle
  • Cooking
  • Drying clothes on a radiator or an indoor tumble dryer
  • Washing machines and dishwashers
  • Baths and showers

Because modern homes are generally much better insulated than they used to be, there are less drafts and less natural ventilation, so no means for the moisture to escape. This is why condensation is more common today. New windows will be completely sealed within their apertures, so this may make a difference if your old windows had air leaks.

What can you do?

You can periodically open some windows to let fresh air in and the moist air out. This is best done by having a window open either side of your home to allow a through-draft. Doing this for a few minutes once or twice a day can have a huge difference, especially after cooking or showering/ bathing:

"The correct way to ventilate a home is to employ the shock ventilation method. You open your windows completely for three minutes if it's windy, five to 10 minutes if it's not,"
(taken from

Well insulated and draft proof homes may benefit from a heat capture system (known as mechanical ventilation with heat recovery or MVHR systems) often referred to as domestic heat exchangers, which bring in cooler outside air while expelling warmer air. The warmth from the stale, moist air is captured and transferred into the incoming fresh air, which provides the least loss of energy. These can be whole home systems (more suitable for installation in a new build or single storey home due to the necessary ducting), or Single room heat recovery units (SRHR) which are designed to provide ventilation to single rooms.

Some further reading on this subject:


Some houseplants are also especially good at absorbing moisture. Some recommended plants are:

  • Spider Plants (Chlorophytum Comosum)
  • Peace lilies (Spathiphyllum)
  • Mother-in-law's Tongue (Sansevieria Trifasciata)
  • Sword or Boston Ferns (Nephrolepis Exaltata)
  • Common Ivy (Hedera Helix)
  • Aloe Vera (Aloe Barbadensis)

For more information, see

We receive a lot of enquiries about the appearance of external condensation particularly in the spring and autumn. Whilst we state in our literature that fitting modern low glazing increases the chances of external condensation, it does seem to surprise many customers. Firstly we need to say that the appearance of external condensation is not a fault in the glass or the windows. The phenomenon is a natural and predictable event caused by the outer pane of the glazing being colder that the glass that it replaced.

With single glazing and older style double glazing a larger proportion of heat was lost to the outside through the glass. With modern low e glass products more of the heat is kept inside and the outer pane is not heated as much. Moisture condenses out of the air onto a cold surface that is said to be below the dew point. The dew point varies with the air temperature and the amount of moisture it contains. In spring and autumn in particular the glass temperature can fall to a low level during the night and the dew point can be comparatively high in these seasons. The glass is more often likely to be below the dew point in these conditions and the moisture condenses onto the surface.

We are all obliged to fit more thermally efficient windows in our homes to comply with the building regulations. There are only a few exceptions to the regulations and they tend to apply to unheated spaces that would suffer external condensation to the same extent anyway. The trend is to use glass that has lower U values over time and the lower the U value the lower the outer pane temperature is likely to be and the bigger the risk of condensation on the external surface. In northern European countries where they use triple glazing with very low U values the phenomenon is understood and accepted. The householders are focused on saving energy and maintaining a comfortable internal environment.

There is not much that can be done to avoid the risk of condensation to the outside. Heating the room more would have an effect but this understandably is not a good option. In many cases the condensation does not last long. A little heat from the sun warms the outer glass enough to evaporate the moisture and a gentle breeze or wind will do the same job.
Self cleaning glass is as prone to condensation as any other glass but the properties of this product means it doesn’t allow the water to form beads on the surface of the glass and so you don’t see the effect to the same degree.

You may notice that not all of the panes are affected by early morning condensation even in the same window. Even subtle differences in orientation and the position of objects outside the window can change the surface temperature of the glass to the point that one pane suffers and another does not. Any object (be it an overhang, canopy, tree etc.) blocking off the window to a clear night sky will also have the effect reduced or eliminated.

A plus point is the knowledge that your windows are keeping the heat in as they are designed to do thus proving that you have a superior insulating glass product.

If you are experiencing condensation to the inside of the room or there is condensation between the panes of glass then there may be a different problem. Misting between the panes indicates a seal failure and the glass should be replaced. Misting inside the room may be as a result of a failed unit seal but is more likely to be the humidity or moisture content of the air in the room being very high, E.g. from a bathroom or kitchen. Bottled gas heaters produce a lot of moisture and even breathing expels enough moisture in an unventilated space to cause the formation of condensation. Increasing the ventilation to such spaces helps control the problem.

The presence of external condensation in a particular season does not mean that the glass will suffer the same throughout the year. Any occurrence is beyond the control of the window supplier and is a natural result of the environmental conditions.

Article from Pilkington Glass

Unfortunately, the unit has failed and will need replacing. Contact us to arrange a replacement.

It is recommended to lubricate all pivot points annually to ensure the continued smooth operation of your windows or doors.

This includes the hinge/ pivot points of windows stays.

With tilt and turn windows there are many pivot points and places where the mechanism slides. All metal to metal contact points should be lubricated annually with a light oil (3 in 1, cycle oil, sewing machine oil). WD-40 or similar solvent based lubricants should not be used to avoid damage to your windows or doors.

Any questions, or if you require a service visit, please get in touch.

Do not use metal cleaners or polish lacquered surfaces, or any abrasive or corrosive cleaners, as these will dull the finish and wear the protective coating.

Wipe with a damp cloth or if necessary a mild detergent solution.

Care should be taken to regularly inspect the door track and to remove any dirt, stones or other debris that could damage the rollers and affect the smooth operation of the door.

This area should be cleaned regularly with a soft brush, warm water and vacuum.

All means of escape windows will open to 90' position to allow easy egress in the event of an emergency.

They come with an easy clean option on the friction stays that allows assistance when cleaning upstairs windows from inside (There is a release within the hinge that can be pressed by hand to release the restriction and allow the window to open to its full extent).

All window openings can be protected from potential risks with auto-latches, kiddy locks, restrictor hinges where applicable.

In most cases, a new hinge or hinges will be required. We are able to obtain a wide range of hinges to suit most requirements. Please contact us to arrange a service visit.

This can be caused by excess moisture within your home. Please see the above FAQ with some advice to avoid this.

To remove the mould, we recommend a 50/50 mixture of Milton tablets/fluid (used to clean baby feeding bottles) and warm water, applied sparingly to the affected area with a soft cloth. This solution is safe and will not harm your window frames, their seals or the sealant used to fix them into place.

This can be caused by debris within the metal tracks of the hinges. This can typically be removed with a soft brush and it is a good idea to vacuum around the area afterwards.

It can also help to lubricate the tracks. This should be done with a light oil (3 in 1, cycle oil, sewing machine oil). Do not use WD-40 or other solvent based lubricants as these can attack the plastics used within your window mechanism.

Window hinges will typically have a small screw that is used to apply friction to the hinge mechanism so that windows do not blow around in the wind. If your window is too tight, it may be that this screw needs to be loosened slightly. Usually only approximately a quarter of a turn anti-clockwise is all that's needed.

Most hinges have a small screw to apply friction to the stay in order to avoid the windows moving unintentionally. Open the window fully to expose the screw and try tightening it clockwise approximately quarter of a turn. This is often all that's needed.

Any problems, contact us for further help.

Polycarbonate and glass roof panels should be cleaned in a similar manner to PVCu frames; washing roof panels with a mild non-abrasive detergent solution, preferably every four months to remove grime and atmospheric deposits. Long handled or telescopic soft washing brushes can be used for easy cleaning of your conservatory roof. Clear gutters of leaves and any other debris as required.

  • Do not walk on conservatory roofs without crawler boards!
  • Avoid solvent based and abrasive cleaners!
  • Avoid leaning ladders against plastic materials which could damage!
  • Do not use power washers on conservatory roof systems!