Our standard double glazed specification provides a centre pane U-value (Ug) of 1.1W/m²K and so when installed into our thermally optimised aluminium frame our rooflights total U-value is just 1.0W/m²K (*).
We offer fully verified total rooflight U-values, so you can be absolutely certain of Building Regulation compliance. Our rooflights exceed the requirements of thermal performance set out in Part L when supplied double glazed, because our thermally optimised aluminium frame is decoupled with double polyamide inserts and continuously foam cored for increased thermal efficiency and glazed with high specification glass units as standard.
There are many well documented benefits of installing building products with lower total U-values. With ever increasing energy prices and governments across the globe introducing initiatives to cut CO2 emissions, installing a rooflight with as low a U-value as possible is a great choice for both the end user and the environment.
For even better rooflight U-values - we offer triple layer glazing with the same high specification features as our double glazing: including warm edge spacer bars and 2 x argon cavities. Our triple layer glazing specification achieves a Ug value of just 0.6W/m²K and is available with both our flat and pyramid rooflights.
When glazed with our triple layer specification our rooflight total U-value is reduced from 1.0W/m²K to 0.78W/m²K (*).
There are plenty of suppliers who offer triple glazing as an option with their flat roof rooflights and we would therefore urge you to request proof of their total rooflight U-values - it is only when armed with this figure that you can make a like-for-like comparison between suppliers. As we discuss in our news article entitled "Uw value - the value which really counts", some suppliers still just quote the Ug (glazing) value in their sales literature and arguments - which is wrong because it is a waste of time (and money) to install triple glazing into non or poorly thermally broken aluminium framework. Any rooflight supplier worth doing business with should be able to produce a data-sheet to substantiate their rooflights total U-value, we calculate ours according to the international standard EN ISO 10077-2:2009 and here's an example (currently in German text only): triple glazed total U-value data-sheet. We are working on translating this document into English - so here is a copy of the data-sheet for our F100 rooflight dome which we have already translated into English: F100 rooflight dome total U-value data-sheet.
* = the total rooflight U-value examples in this article are based on our FE rooflight to suit a roof opening size of 900x900mm supplied with our 150mm high fully insulated upstand.
For more information about our range of rooflights please refer to our website, email us or give us a call on 01284 749051.