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Building Regulations and Window Energy Ratings

Unglazed Frames

8) Declare EN1279 part 5 Annex ZA

As part of the WER application process, the Window installer/fabricator is now required to supply a declaration to EN1279 part 5 Annex ZA for their chosen IG supplier. Therefore, if the IG manufacturer has not already registered this declaration with the BFRC, CERTASS or other competent persons body they are urged to send their EN1279 part 5 Annex ZA declaration to relevant customers.

Approved WERs may be published on a registered WER list subject to a fee for each individual entry.


For a standard letter template Click Here. We can provide an editable version of this letter on request.

Building Regulations and WERs Page 14

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