CEN TC 129 - Glass in Building

Mr Wiegang was able to work on different issues, and participated to several meetings of different WGs such as:

• WG 3 - Laminated glass. The main issue was the definition of a product family: a product family is a group of products which is made with the same interlayer type (polymers for folio and/or cast in place lamination, intumescing) and which is tested for FPC using the same test method. This proposal has been restructured the individual definitions of EN 14449.

• WG 6 – Coated Glasses. Reduction of the tolerance on the emissivity for the low-e coated glass, but not for the other coatings. This was a proposal from NPME expert as large tolerances lead to inaccurate data product specifications, and, consequently, to dispute.


• WG 8 – Mechanical Strength. The shear resistance was investigating. One thrust of the network approach in the design of the glass panes usually leads to a reduction of the required glass thickness. This is particularly important for SME's – as it is of crucial importance for the mounted enterprises. Was examined, the effect of temperature change on the rest structural behavior. The standard will be the assessment base for the calculation of glass in buildings. The CEN/TC129/WG8 document, which compares the results of a series of thermal safety checks undertaken, using the UK and FR DTU methods, was discussed. There was a general feeling among the members that the proposed methods (in their current versions) gave results which were too divergent for them to be both incorporated as alternative calculation methods in a standard. The members indicated some of the ways in which the two proposals differed. Before further progress is made, the committee needs to have a better understanding of the differences between the two methods and whether there is potential for reducing these differences.


• WG 12 – Glazing Rules. During the revision of the draft EN 12488, a number of objections and changes came from NPME expert. This standard describes a significant part of the work for a window manufacturer. prEN ISO 14439 makes reference to 2 contradictory standards about terminology: EN 12519 and ISO/CD 13316. The convention to show the way a window is open is the opposite. This will create a lot of confusion for Annex A, as the opening should be indicated on the drawings. Because of that, WG12 is considering the possibility to transform EN ISO 14439 in a full CEN standard, for instance EN 12488-3. This will also be discussed during the ISO plenary in November 2011.

For more information, contact the TC coordinator Mr Lorenzo Accardo (l.accardo@normapme.com) or the TC expert Mr Lutz Wiegand (wiegand@eurowindoor.org).