It’s a well-known fact that replacing single glazed windows with double or triple glazed units will increase the energy efficiency of your home, reducing it by up to 10% in some cases.

What you may not realise is that it’s also an effective way to improve overall comfort, by preventing cold draughts and cutting out sounds from outside like traffic.

Plus, with a whole range of stylish coloured uPVC frames, aluminium options and classic wooden ones available, there’s now a massive choice of styles to both complement and improve the existing look of your property.

If you’re thinking of installing new windows, or adding an extra room to your home with a conservatory, use this guide to help you choose the right installer.

What they do

Window and conservatory installers can transform your home by adding new windows and conservatories (uPVC, aluminium or timber), or upgrade and repair your existing ones.

They will also repair rotten wood, replace broken cords, upgrade glazing, install draught seals and security locks and renovate timber frames.

Most window and conservatory installers are also trained glaziers whose job involves:

  • Choosing glass
  • Removing broken panes, beading and putty
  • Fitting new glass and making sure the sealing is watertight
  • Making decorative glass panels

They also need to fully understand fire safety and building regulations when planning and installing.

What they charge

Installing new windows in a large property can cost upwards of £10,000 or as little as £100 for a new double glazed unit to be fitted to an existing frame.

The materials you choose will have the biggest effect on your budget. Wood effect uPVC frames cost around 20% more than standard white frames, aluminium frames can cost around 50% more than uPVC frames and A+ rated glass (that’s the most energy efficient) will cost around 10% more than B rated.

A few example prices are as follows:

  • Single open white uPVC casement window (600mm x 900mm) – from £200
  • Single open sash wood – £500
  • Full house casement white uPVC (12 windows) – £5000
  • Full house sash wood (12 windows) – £10,000
  • Victorian conservatory (3.5m X 3.5m) – around £13,000.
  • Gable fronted conservatory (3.1m X 3.1m) – £12,000

What to ask

Here are a few questions to ask your window or conservatory installer to ensure you’ll get a good job at the right price:

  • Are your windows or doors rated by British Fenestration Rating Council (BFRC)? This is the premier authority responsible for window and door energy ratings in the UK
  • How long are the windows guaranteed for? Good quality uPVC windows can last over 30 years and aluminium a couple of decades longer, though warranties are often shorter
  • Is the work guaranteed?
  • Will you manufacture the doors or windows to my home’s exact specification?
  • What kind of frames do you specialise in?
  • Do you have a showroom where I can see the products?
  • Will my deposit be protected by a third party such as the GGFi?
  • Are your products CE marked?
  • How long will the windows take to manufacture? (this will normally be around four to six weeks)
  • What’s your aftercare policy?

Before you sign a contract to buy any replacement window, doors or roof lights, be sure to ask whether the installer is able to self-certify. If not, an application to your local authority building control for approval under building regulations will need to be made by either the installer or the homeowner before any installation work can commence.

Trades to trust

FENSA is the competent person scheme that is trusted by the industry. As part of their commitment to maintaining high standards, FENSA carries out random inspections of its registered installers, which include tests during installation and after the windows have been fitted. Use a FENSA certified installer and you will automatically receive a FENSA certificate that will state that the installation complies with building regulations.

The Glass and Glazing Federation (GGF) represents companies who make, supply or fit glass and glass related products in the UK and internationally. The GGF plays a large part in the setting of new standards and regulations, such as building regulations – the rules that govern and control the way our buildings are constructed in the UK.

The law

Replacing windows and doors now needs to meet certain standards in the building regulations to reduce energy loss. This means that you need to comply with the building regulations when installing replacement windows, doors, or roof lights in domestic buildings. A certificate from FENSA or from your local authority building control, issued when they were installed, will prove this.

You may need planning consent to install replacement windows in a conservation area.

Ready to hire?

3 is the magic number

As always, try and get three quotes from three different window and conservatory specialists to ensure you pay a fair price for the job.

Certification and references

Don’t be shy about asking for any relevant certification, proof of public liability insurance and references or photos from previous jobs. If the window and conservatory specialist is trustworthy and competent, they’ll be pleased (and proud) to show you both.