Double Glazing FAQs

Answers to all your double glazing questions

Premier Windows is growing to be one of London’s leading local double glazing companies, largely due to our commitment to making the buying experience as transparent as possible. If you are looking for a friendly and reliable window and door installation service, you’re at the right place.

With 20 years of industry experience, Premier Windows is the local company you can rely on. We have carried out countless home improvement projects for a long list of satisfied customers and many local authorities.Nothing has changed when it comes to our approach to customer service — we’re here to offer effective solutions for your window and door requirements while simultaneously putting the customer first and delivering fantastic service every time.

With any new buy brings a multitude of questions, from learning about what your options are to making the right choice and knowing what to expect afterward. Every customer’s product has its own unique material, style and glazing system, so there is absolutely no question too big or too small — in fact, you may learn something new before you even know you want information about it.

All of our products come with a 10-year guarantee and are fully accredited and sustainable. Along with minimal maintenance and upkeep, we are confident they’ll easily outlast the guarantee period.

If you have any questions about your upcoming installation or new double glazed windows or doors, check out our frequently asked questions below. Click on each question to reveal its drop-down answer. If the below FAQs don’t answer your questions, we’re happy to help — give us a call on 020 8683 4446 or send us a message and we’ll get back to you promptly.

To expand on these FAQs further, take a look at our blog, which is filled with informative articles on how to improve your home.


Product Information

Will my new windows be exactly the same as the old ones?

A new window frame depth is 145 mm, which is the slimmest option possible due to the 2 mm double glazing. No supplier can offer 24 mm glazed sashes in frames with a depth of less than 145 mm, so these new windows are as close as can be to existing traditional single glazed windows, which were used in the past.

Can I use my existing original leaded windows or stained glass in your frames?

Yes, we can install most lead stained glass or leaded glass panels into our frames.

Do your windows and doors come with energy efficiency ratings?

All our products we supply are A and B rated and comply with all energy efficiency standards.

What draught proofing do you use for your windows and doors?

We use rebated brushes fitted to the top, bottom, midrail and both sides of all installations (all concealed).

Are your products disability and wheelchair friendly?

Our replacement door thresholds can be modified to accommodate wheelchair access. We can also fit automatic window openers or manually winding openers to your windows while retaining energy efficiency and security.

What are the specifications of your double glazing?

Guardian glass 24 mm overall (4-16-4) with argon gas, white spacer bar as standard, Low E soft coated, U value of 1.4.

We would like uPVC sash windows, but we don’t like the plastic look. What are my options?

We can supply a upvc woodgrain effect frames with timber surround, which will be more in keeping with your existing furniture and upholstery.

What is a “sash horn”?

A sash horn is a decorative item, which is added to windows to match the elegant design of a traditional look.

What is the difference between “sash” and “casement” windows?

Sash windows are more traditional and slide up and down, whereas casement windows give greater flexibility and have “openers” that can be pushed out or tilted in.

What are sash window pulleys and sash cords made of?

The pulleys are made of stainless steel plated in chrome or brass. Sash chords are made of nylon (either 6  mm or 8mm depending on the window size and sash weight).

Do you use treated timber?

Yes, all of our timber is treated with Teknos Aqua 1410-01 for Softwood and anti-stain Teknos Aqua 2901-01 for oak. All timber products, including the bottom of sills, is treated with impregnator, primer (Teknos 3130) and two top coats.

Do timber effect sash windows look the same as real timber?

We use our own high-quality custom-made decorative finishes for our uPVC timber effect windows, which gives them a very realistic effect. We can match your new windows to existing window and door frames so they look indistinguishable from a distance.

Can you match any timber finish or do you supply dual colours?

Yes, timber finishes can be matched and we can supply dual colours, including RAL colours.

What type of timber are your sills and frames made from?

Our sills are made from European Oak and the frames are made of either Hardwood or Softwood timber.



How long does it take to install windows and doors?

This often depends on the condition of the site and how complicated it might be. Usually, a two-man team of fitters will complete three to six windows per day.

Do you have your own installation team fitting your windows?

Yes, we only use our own fully trained and accredited installers for all of our jobs.

How soon can you install my product?

Before you order anything from us, we will contact you (usually within a week) to discuss fitting our installation into your schedule. After receiving a confirmation of sale with a signed contract and cleared deposit, your installation will usually commence within two to three weeks for uPVC and eight to ten weeks for timber. This can fluctuate a little from time to time depending on our suppliers and how busy they might be.

Do you dispose of the windows after installation?

Yes, we always dispose of the old windows, glass and any rubbish that is left over from your installation. All recyclable material is recycled in our own recycling plant. We will also ensure that your home and property is vacuumed if required and protected with dust sheets to leave it as clean and tidy as it was before we arrived.

Will our curtain rails fit back after we have had your windows installed?

Curtain rails, blinds as any existing timber shutters should fit back onto the new windows,but they may work differently as they are not measured to fit onto

Will my carpets or tiles be affected by having a new door installed?

Once we have seen the proposed site, either in person or by photo, we can give you more specific information about your project. However, we always aim to leave all premises in the same condition as when we arrived.

When removing window and door frames, will it affect any wiring or electrics in my home?

Most of the time, this isn’t an issue. If we come across wiring when we are installing for you, we will have to stop work (or continue in a safe area) and you will need a qualified electrician to make it safe for us to continue working. We are not allowed to work with any wiring at all.

Do you need to construct scaffolding?

This depends on the building in which we are fitting windows. In the interests of your home, your safety and our workmen’s safety, we must strictly adhere to current Health & Safety regulations.


Safety and Security

What level of security do you supply?

Your timber windows come with key-locking fitch fasteners as standard, and ROLA child locks are also available if required.

Is it possible to order spare sets of keys or replacement keys?

For security and legal reasons, neither us nor our suppliers are allowed to keep copies of your keys. The best way to get additional keys is to see a locksmith. If you have lost your keys, you will need to purchase a new window handle (with new keys) or a new barrel for your door lock (with new keys) and have a locksmith fit and replace these for you.

Could a burglar take out my glass and gain entry via your windows?

No, our Premier range is internally glazed, which means the glass can not be taken out from the outside unless it is broken. Glass can only be removed from the inside.

Do your windows provide any child safety?

Yes, we have many different solutions for safety and security depending on your needs. A member of our team will advise the best solutions for you at the best price.

Do I need to make allowances for fire escapes, just in case of an emergency?

When arranging a site visit, our consultant will advise on what is required to comply with Health, Safety & FENSA regulations.



Is obscure or decorative glass difficult to clean?

No, as the pattern is on the inside of the pane. The outside panes of obscure or decorative glass are smooth for easy cleaning.

Do you have a sash window that tilts inwards to clean?

Yes, but you cannot have sash horns as well because they get in the way of the tilting frame.

When I sleep at night my windows go all misty. Why is this?

This only happens if your room or house is badly ventilated. When purchasing your new windows from us, we can insert trickle vents, which can be opened or closed to ensure your room is ventilated properly. It is not healthy to have unventilated rooms. Our vents also have insect screens to ensure no bugs or insects can join you in the night.


Sound Proofing

How effective are your windows in terms of sound proofing?

Our standard windows have Pilkington 4 mm-16 mm-4 mm Krypton gas-filled glass units, which will meet most soundproofing and acoustic requirements.Other options include:

  • Laminated glass 6.4 outside
  • 14 mm gas-filled gap and 4 mm toughened glass units
  • Pilkington Optiphon, which comes with laminated units

Our double glazing has been installed, but the noise outside is still too loud. What can I do?

We can help you with this problem, as we have done for studios in the past. Secondary glazing (small aluminium frames with glass that is made to be as seamless as possible) is a common solution for this, though the effectiveness will depend on the quality and state of your existing windows. Upgrading to double glazing is a surefire way of improving the sound insulation of your property.

Is triple glazing my best option in terms of soundproofing?

Absolutely not. Triple glazed units are designed to increase heat saving and, therefore, do not increase soundproofing at all.


Planning Permission

Can you supply windows for use in UK conservation areas?

We can supply windows suitable for conservation areas across Greater London. It is essential that you check with your Local Authority regarding the status of your property in terms of conservation. Sadly, we are unable to enquire on your behalf.

Do I need to get planning permission before installing windows and doors?

You do not need planning permission to replace existing windows or doors, though you will need to check to see if you are located in a conservation area, as you may be restricted with what designs or materials you are allowed to replace the existing windows with. If you are building an extension, you will need planning permission. Please confirm these details with your local council, as these laws are subject to change and we cannot accept any liability for any errors made in this regard.

Do your products meet British standards?

Yes, our products not only meet ALL British specifications and standards but far exceed them. For more information about our accreditations, please email or call us and we will be happy to advise.



How competitive are your window prices compared to others?

All of our prices are highly competitive due to our unique buying power. As we supply and fit 30-40 windows per week, we can bulk-buy your windows and pass the savings onto you.

Can you provide an estimate over the phone or by email?

We are happy to give you a quote via fax, email or in person. We can also send one of our surveyors to your home to measure up and discuss your needs and options. If you can supply digital photographs of the existing windows, we can provide our best price based on these photographs alone. This is what we need from you in order to complete a quote:

  • Number of windows required
  • Approximate sizes in mm
  • Style of window (preferably drawings including number of openers, Georgian bars, etc.)
  • Supply only or supply and fit (whether you require our fitting team to install the windows)
  • Material (uPVC, timber, aluminium, etc.)
  • Contact details (full name, address, site address and telephone numbers)

Do I have to pay the full amount when I order?

After making your order, you will need to put down a 25% initial payment (or £400, whichever is higher) when you order, following 50% interim / delivery payment and the outstanding balance is payable on the day of satisfactory completion. Storage charges may apply if you delay the installation.

What happens next?

If you decide you would like to receive a quote from Premier Windows or discuss your possible installation further, you can request a free call back or arrange a no-obligation quotation by using this contact form or by calling us on 020 8683 4446 today.