Frequently Asked Questions

Frequently Asked Questions

See below for a list of our frequently asked questions:

What is a trickle vent?

A trickle vent is a very small opening in a window which allows a small amount of ventilation in to a building. They are integrated in to the frame of the window to provide the minimal ventilation that is needed. They help to avoid problems that are associated with poor ventilation, e.g. reduce risk of condensation, avoid over ventilating which minimizes energy consumption and there is also an improved comfort through draught avoidance.

A trickle vent is only used on windows going in to a new build or a window that is new to an existing building. Replacement windows do not require them unless you request it. Check with your builder or Architect to ensure correct sizes of trickle vents are installed.

What is a sash horn?

A sash horn is an extension of the sash side frames in a sliding sash window. The purpose is to provide extra support for mid rails which are often very narrow. The second reason for using them is to give authenticity to your windows and meet conservation requirements. There are many styles and it is best to match as close as possible to originals. Sash horns are generally on the exterior of the top sash however they may be supplied on the lower sash and will be visible on the interior of the window.

What does aluminium cladding on a wood window mean?

Cladding is an aluminium skin attached to the exterior of a wood window to provide protection from the elements and eliminate need to paint or varnish the exterior of the windows. It fulfils the low maintenance function of PVC whilst retaining the wood interior so you can benefit from the warm wooden interior and no added maintenance costs.

How do I maintain the paint finish on my windows and doors?

Good maintenance of your windows can help to retain their shape and strength for many years. When the timber surface is to be cleaned, it is a good idea also to have a look for any small cracks and crevices in the paint surface. Especially the windows on the south and west-facing facades as these are the most exposed to the sun and weather. If the protective surface has cracks or fissures through to the wood, It is recommended that you repair the damage immediately.

Generally, when the weather begins to discolour the paint on your windows and doors, it is time for re-painting. Follow the manufacturers recommendations to get the best results.

If you have bought aluminium clad windows maintenance is very limited. You can make do with washing them outside a few times a year, but it is best if it becomes a habit to wash them when washing your windows.

Condensation on the window pane

Dew on the outer side of the glass is positive as this is proof that the window is very energy efficient, and that it functions properly.
In certain weather types, for example a clear frosty night, when there is more heat radiation from the earth towards the sky there may be periods in the early morning hours where the outer surface of a low-energy pane is colder than the air outside. This results in condensation on the glass surface. The dew disappears when the air temperature rises during the day.

If there is condensation on the inner side of the glass, you will need to ventilate the room. It is a sign of too high relative humidity inside and should be reduced to prevent rot, moisture damage and a poor indoor climate.

Dew between the two pieces of glass is a sign that the sealed glass unit is punctured and should be replaced.

Will new windows reduce noise levels from outside?

Modern double-glazed windows will generally offer noise abatement options such as different thickness glass panes and use of laminated glass. This cuts down noise transfer, so you hear less noise inside your home, for a more peaceful, relaxing lifestyle!

How long will it take to install my windows?

Exact time depends on the number and style of windows. But as a general rule, a whole house (8-10 windows) should be fitted in 2-3 days. Your window supplier should carry out a full survey before the new windows arrive and will therefore know the extent of work required.

Carrying out the survey also means they will have manufactured all the replacement windows to the exact size needed to replace the old frames – again minimising time on

How can I tell if a window is energy efficient?

CE marked windows will indicate the U-value of the full window including the frame. The U-value marking is the indicator of heat transfer through your window. This can vary quite a bit however ratings down to Passive Level are now widely available. The CE ratings are now legally required to be provided on all windows used in UK and Ireland. Also look out for the British Fenestration Ratings Council (BFRC) Window Energy Label. This is similar to the one you may have seen on your fridge or washing machine. A+ rated windows are the most efficient products and will benefit your home.

What will happen to my old windows?

Your window supplier should be able to deal with the old windows. If they’re made from PVC-U then they can be sent to a recycling facility where they are used to make new energy efficient products.

How can I make sure my windows have adequate security features?

If you’re worried about your home being a potential target for burglars, then it’s definitely worth asking your window supplier if the company’s products are Secured by Design (SBD) accredited.

SBD is an official UK Police initiative supporting the principles of ‘designing out crime.’ If your window supplier has this accreditation it means they are authorised to supply windows and doors with an optional Secured by Design endorsed upgrade that includes extra security. For more information on Secured by Design, visit

What guarantee should I ask for?

Most companies offer 10 years on frames and glass. This is what you should expect as standard

Will I need to re-plaster inside my house?

Some minor plaster work may be required around the window reveals, although your installer should carry out this work.

Will I need to remove window dressing such as curtains?

Yes, you will need to remove these to allow the installer clear access to the windows

Do I need planning permission for windows?

Planning permission is not normally required for repairing, fitting or replacing doors and windows, unless you own a listed building. If you live in a conservation area (or other designated area) you should consult with your local planning authority. Visit for more information.

How should I clean the frames?

Normally, a soft cloth and warm soapy water is all that is required to remove dirt and grime. If you want a professional quality finish, Abrasive cloths and solvents should never be used to clean PVC-U, as they will damage the surface finish of the profile.

Can I keep our existing wooden window or door frame?

If your window frames are in very good condition it is possible to replace only the glass elements. However it is difficult to ensure that you get a guaranteed thermal performance when only replacing glass as so much will depend on the skills of the people doing the work. Your existing frames may not be capable of taking modern wide gaps between the panes and if your frames subsequently fail then the new glazing is wasted.

What is Low E?

Low-emission glass (Low-E) is a clear glass, it has a microscopically-thin coating of metal oxide. This allows the sun’s heat and light to pass through the glass into the building. At the same time it blocks heat from leaving the room, reducing heat loss considerably.

How much does double glazing cost?

We offer a bespoke service so just as every home varies so will the cost of made-to measure windows. The price will depend on the material you select and the size of the windows you need.

The beauty of a bespoke window is that it will be perfect match for the space. Unlike standard size off-the-shelf windows, there is no need for additional fillers and packing materials that allow precious heat to escape.

How does double glazing work? How does double glazing prevent heat loss?

Double glazing prevents heat escaping by using two panes of glass filling the gap with argon gas, which minimises the heat lost through heat transfer. Adding in a low-e coating to all the inner panes will reflect heat back into the home.

Double glazed windows can also be fitted with ‘warm edge spacer bars’ which are made from a less-conductive material than conventional aluminium spacer bars.

What is low-e glass?

It’s a soft coating that’s applied to the inner pane of glass within the sealed unit. It enables heat from outside to pass through your home, but stops heat from inside escaping outdoors. You should insist on Low E coating on your windows.

How long does double glazing last?

As with everything this will depend on how well you take care of it. Carry out maintenance in accordance with the manufacturers instructions to get the longest life for your windows.

How to install double glazing?

We strongly recommend you use a professional installer to fit double glazing The best procedure is to buy from a supplier who also installs; that way you have one person to deal with rather than be caught between various parties blaming each other if a problem arises.