C rated Window Frame and A rated Glass = B rated window?

[ik1]

Hi,

Can I please check with you knowledgeable people about double glazing.

I have a local company that quoted me C rated Deceuninck profile and A rated glass.

Now the question is does this equate to a B rated window? and can they make the the frame more energy efficient, so that I have A rated frame and glass using this profile?

Many thanks for your help

 

[Gazman16]

Ask them what the overall window rating is. They should know as its a legal requirement to be able to prove the overall window rating.

You can make pretty much any make of window A rated by putting the right glass in (and paying thousands to have it tested), You actually lose more heat from the frame than the glass as a general rule.

Are they talking about doors rather than windows? Doors at the moment don't have to be tested in the same way as windows.

 

[ik1]

Thanks for the reply.

I got a paper with the drawing of the Windows and it just mentions in the notes, C rated frame A rated glass but I will clarify with them.

How much of a difference is between A, B and C because the price they gave me is good but is it worth me paying extra for Argon filled gas when the heat loss will just happen through the frame if its not at the same rating?

Thanks

 

[ik1]

Does anyone know if the frame rating affects anything other than heat loss, such as noise?

Also how much of an energy loss is it between C, B and A ratings, if its about few pounds a year then I am not too bothered but if its more I can at least try to get A or B rated frames.

Thanks for you help.

 

[Gazman16]

In theory the more chambers a frame has the more thermally effective it is, I guess this would also increase the sound proofing.

Most standard PVC profiles have 4-7 chambers, Unless you went with something like a Residence 9 windows that is 100mm thick and has 9 chambers (its also 3-4 times the price of normal windows).

Here is something I got from one of the glass manufacturers that I used to give to my customers to help them decide on ratings:

A,B or C rated windows?
What is the average saving to householder between A, B & C rated windows in terms of energy and cost savings?
A, B and C rated windows are all much more energy efficient than standard windows. That said, there are differences in performance of energy efficient windows with A B and C ratings;
• Changing existing single-glazed, timber windows to Band C windows in a semi detached, gas fuelled house would be expected to save £4350 in heating costs and 11 tonnes CO2 over 20 years.
• If the new windows are instead B-rated then the savings increase to £4650 and 11.5 tonnes CO2 .
• And, if the new windows are instead A-rated then the savings increase to nearly £5000 and over 12 tonnes CO2 .
The above shows that achievement of the level C displays significant savings over existing windows with higher ratings of B and A delivering further smaller incremental savings above C.

The only physical difference between our A & B rated windows is coating on the glass and the gas inside the unit.
Using the above example fitting A rated rather than B rated would save about £350 on heating bills over 20 years which is a £17.50 saving per year.