Other options that affect the cost of double glazing
Apart from the style and material of a double glazed window, there are other factors that will impact on the cost of new double glazed windows.
Size - it might seem obvious but a large living room picture window is going to cost significantly more than a small toilet window.
This is the main reason why it's so difficult to answer the question of how much does double glazing cost.
Energy rating/quality of glass - glass might look all the same but there is a huge difference between the quality of energy efficiency performance.
When buying new double glazing look at the thermal efficiency, the solar gain and the air leakage values. A window rated at least A+ means it is highly efficient across all of the above and should be what you choose to make the investment in double glazing worth it.
Furniture and finish - door handles, locks, number of opening windows, colour and any grain effects all need to be factored into the double glazing cost.
Cheap windows might not include extras and you will need to pay more for upgrades to get the handle or locks that you want. Don't underestimate how much the finishing touches can add to a basic price.
What should your quote for double glazing include?
If you're comparing the average cost of double glazing from different companies and want to know how much does double glazing cost, make sure you are comparing like-for-like.
As we highlighted above, there are many variables to consider that can dramatically alter a price. Even factors like installing in an upper floor that would require scaffolding have to be taken into account.
If you do want to compare quotes then make sure your double glazing cost quote has the following:
- A full technical survey with drawings
- Full product details of size, style, colour etc.
- The number of windows
- The window energy rating (WER) for the glass
- Any additional features, such as handles and locks
- Does it include external window sills?
- When does the work start and finish?
- Disposal of your old windows
- Warranties for installation
- Guarantees for products
- Company details and accreditations (see below)
What double glazing accreditations and standards should I look for?
Building regulations do apply to double glazing window replacement so you must use a reputable company that is registered under the competent person scheme. They give you a certificate of completion that states your windows pass regulation otherwise you have to obtain build regulations permission yourself (at additional expense).
The accreditations to look out for include:
- Competent person scheme CERTASS
- Fenestration Self Assessment Scheme FENSA
- British Standard Institute BSI
- The Glass and Glazing Federation GGF
- Secured by Design, the official police security initiative SBD
You can read about Everest accreditations here and an explanation of CERTASS here.