In my February Tech Talk column, I updated my guide to the standards affecting the manufacture of door sets. This time around, I’m focusing on windows, and the changes which have come into play since I last covered this in Glass News back in 2014.
PAS24: 2016 (supersedes PAS24: 2012)
This is the current security standard for windows in the UK and it certifies that a particular window and hardware set has withstood a series of physical tests based on the common methods of burglary. The tests include: infill mechanical test (trying to push the glass out), mechanical loading of the locking points, manipulation test, manual test (attacking the window with tools) and infill manual test (trying to deglaze the window from the outside).
The standard is split into 3 parts: Part A – Security hardware and cylinder test assessment, Part B which applies to doors and Part C – Enhanced security performance for windows.
The main differences for windows between PAS24: 2016 and PAS24: 2012 are:
- The scope has been widened – 2016 includes more designs of windows, including vertical and horizontal pivots
- Entry criteria – if an aperture of 50mm or greater is created during any of the tests the window is classed as failed. This used to be 225mm x 380mm in PAS24: 2012 on a window using a removable key. This is a big change as on windows, if the locking point is not within 100mm of the corner of the window, the actual corner is tested and profiles can easily be bent in excess of 50mm to allow the cylindroid to pass through.
- The classification has been simplified – window sets were previously classed as either WK (window with key entry) or WKT (window with or without key entry) but in PAS24: 2016 they are all classed as W.
- At least one pane of laminated glass to class P1A or higher is now required in windows adjacent to doorsets, regardless of whether they are fitted with key locking handles or not.
BS: PAS24: 2012 (standard withdrawn)
Although PAS24: 2016 supersedes PAS24: 2012, the building regulation Approved Document Q still references PAS24: 2012 so, at the moment, fabricators can choose to test their windows to either 2012 or 2016.
You’ll see from the differences I’ve pointed out that this can be significant, especially when it comes to the entry criteria.
It is worth noting as well that, to claim conformity to PAS24: 2016 or 2012, windows must be classified according to their intended use for all relevant characteristics in accordance with BS 6375 (all parts, see below) and must meet the requirements of the relevant material specific standards such as BS 7412, BS 4873, BS 6510, BS 8529 and BS 644.
The old window security standard BS7950 which came before PAS24: 2012 did not require any performance testing so, in theory, a window only needed to be closed once in order to pass the test. It didn’t take operational characteristics into consideration so a window might have been secure but you may not have been able to actually open and close it and it could have leaked air and water.
BS6375 – 1 Weather testing
Tests include air permeability, water tightness and resistance to wind load.
BS6375-1 does not state a recommended performance level for windows or doors but it does have a minimum UK exposure category of 800 to allow a product to be registered.
BS6375 – 2 Performance of windows and doors
This sets performance requirements for the strength and operation of manually operated windows.
Tests include operating forces, mechanical strength, resistance to static torsion, racking, load bearing capacity of safety devices, impact resistance and resistance to continual opening and closing.
In the test, windows are repeatedly opened and closed between 5,000 and 20,000 times.
BS6375 – 3 Classification for additional performance characteristics and guidance on selection and specification
BS6375-3 covers the characteristics of BS EN 14351(CE marking) that are beyond the scope of BS6375. These characteristics may or may not be required depending on the required function of the product being tested.
Tests include: resistance to snow and permanent loads, fire characteristics, dangerous substances, ability to release, acoustic performance, thermal transmittance, radiation properties, durability, bullet resistance, explosion resistance, behaviour between different climates, behaviour under humidity, burglar resistance and power operated products.