Typical make up of laminate glass
Laminated safety glass is manufactured by sticking two or more pieces of glass together using either a resin or pvb (plastic) interlayer. A typical make up would be 3mm glass/0.4mm pvb/3mm glass. This would commonly be known as ‘6.4mm laminated’.
Protection from life threatening cuts
When broken the glass stays in one piece being held together by the pvb/resin interlayer. This is the same as car windscreens and when broken, a typical ‘spiders web’ pattern results from the impact. This gives protection from cuts as the glass is in one piece.
Laminated glass can be made up of multiple glass/interlayers giving varying strengths and functions. This ranges from added security and noise control through to ‘bullet proof’ glass.
Toughened laminate is available to order and this offers the additional benefit of added strength with security. Toughened laminated is 2 pieces (or more) of toughened glass, laminated together. It is available in various combinations e.g. 4/1.5/4 = 9.5mm. Due to the toughened make up, this type of laminate is specific cut sizes only and not cut from larger sheets.
Additional benefits of one piece laminate glazing:
- Prevent ingress of dangerous objects – through glass roofs for example.
- Offer a barrier protection element preventing people falling through – balustrades in shopping centres offer this.
- Block up to 99% of UV rays offering protection in large glass areas – slowing UV degradation of furnishings in conservatories or shop fronts.
New PAS 24:2012 & Secure by Design – SBD glass specification
Current SBD requirements indicate that glazing where required must meet: ‘Glass in building. Security glazing. Testing and classification of resistance against manual attack’ with a P1A Performance classification.
This means that all SBD accredited doors and windows must have glazing that conforms to this level with ‘standard’ 6.4mm laminated glass no longer being suitable. Therefore Glasscraft now stock 6.8mm laminate that has accreditation to P2A and thus is superior to P1A products. See download opposite for more information.