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Why its time to change your locks.
Published by Admin - PPM Locksmiths in Upvc Doors • 09/08/2011 07:07:19

For decades, double-glazing salesmen have been extolling the virtues of uPVC to an unwary public. The very first windows were constructed with beading on the outside, which meant that an intruder could remove the glass panels to get in. The first doors, about forty years ago, had three-point roller mechanisms that were praised for being “more secure than a mortice lock”. That is, until someone happened to lean on the door, at which point it would spring open.

In response to these ‘design faults‘, manufacturers made windows with internal beading, and that seemed to offer a more secure solution. For doors, they introduced multi-point locks with more rollers and a deadbolt - a five-point mechanism - only to discover that a burglar could ‘unzip’ the door with a screwdriver and get in.

So in response to these continuing ‘design faults’, manufacturers started to produce locking mechanisms that employed mushroom rollers, shootbolts and hookbolts, which meant that, at last, burglars couldn’t prise the door open.

For a short while, the rate of burglaries to uPVC doors actually decreased and, with the general public now convinced that uPVC was their best option, these improved doors were fitted on the great majority of homes in the UK.

Unfortunately, one of the greatest ‘design faults’ of uPVC doors has never been properly addressed, and now the word is out. There are thousands of unqualified people scraping a living, advertising as locksmiths, with just one tiny piece of knowledge - the best and easiest way into a uPVC door is through the cylinder. It seems inevitable that, once a secret is passed on to unqualified people, it is only a matter of time before that secret is discovered by the criminal element, and spreads like wildfire.

In 2010, there was a 14% increase in domestic burglaries, with a huge increase in the number of forced entries via cheap and basic cylinders on uPVC doors. Countless thousands of homes in the UK have excellent locking mechanisms on their doors, costing hundreds of pounds to stop the door being prised open, but operated by a cylinder costing as little as £5, which offers absolutely no resistance to burglars. What is worse is that the vast majority of unqualified individuals offering their services as locksmiths continue to replace cheap and basic cylinders with the same (and often worse) cylinders that serve no useful purpose. A lock is meant to keep out intruders - these basic cylinders won’t.

So, in an age when we strive for the energy efficiency that double glazing offers, why is the security of uPVC doors prone to such ‘ design faults’?

The answer is simple - uPVC doors were never designed in the first place. They evolved almost by accident, employing elements that were produced for other purposes.

In the early part of the 20th century, the engineering company started by Carl Zeiss was world famous for its cameras, but subsidiaries offered products employing highly skilled engineers in other fields, such as lock manufacture. Under the Zeiss Ikon banner, their locks were internationally famous for innovation and precision.

In 1924, a Zeiss engineer, Sylvester Wohrle, invented a back-to-back double cylinder lock for steel doors. The Zeiss company was awarded a patent in 1927 for this innovative lock which was designed to be changed quickly and easily, fixed with one screw on the edge of the steel door. It gained favour throughout industrialised Germany because the main part of the lock could remain, but the key mechanism could be readily replaced in little more than seconds.

It is precisely the same cylinder that is used in uPVC doors today. Amazingly, the original prototype developed by Zeiss over 80 years ago is probably more secure than the vast majority of modern profile cylinders, but there was no ‘design fault’. The profile cylinder was never intended for anything other than steel doors.

In 1926, Waldo Semon, working for the American B. F. Goodrich company, was employed as an industrial chemist in the search for a viable substitute for rubber. The United States had aspired to overcome its dependency on imported materials wherever possible. Vinyl had been invented almost 100 years before that, but no one had found a practical use for it in its unplasticised form. Waldo Semon developed additives, and a method to plasticise the material which meant that it could be employed in commercial applications. The full name for vinyl is Polyvinyl Chloride, or PVC. In its unplasticised, or rigid form, it is called uPVC.

uPVC was first used for making pipes in 1932, and as a cheaper and equally durable alternative to aluminium and lead piping and guttering, production was increased. By the late 1950’s, in response to post-war shortages of timber, aluminium and rubber, it was being used more generally as a building material, for cladding and fascias. New extrusion techniques introduced in this decade increased the applications for uPVC products.

Due to world shortages of timber during, and immediately after, World War 2, fast growing softwoods were often used as building materials. Much of this was not properly treated against weathering, and needed a lot of maintenance. The immediate solution to this was aluminium. By the 1960’s, the supply of aluminium had been stepped up, and in the USA and mainland Europe, doors and windows using extruded aluminium became commonplace.

The big problem with aluminium is that it is a poor insulator. Houses fitted with aluminium doors and windows tend to be much colder than those with wooden windows. By the end of the 1960’s, the world was ready for the insulating properties and the relative cheapness of uPVC.

If you go back to this time, it is impossible to find out who was the first to use uPVC to make a door, and who was the first to use a multi-point lock mechanism operating from a profile cylinder. If you could go back in time to trace the first use of uPVC for doors, you’d perhaps find that someone ordered aluminium, but changed their mind because of the price, so the lock and cylinder were transferred to uPVC.

There’s no real benefit in speculating why it happened, but one thing we can say is that, with all the ‘design faults’ that have come to light since it was first introduced, the locking system was never designed to be used in uPVC doors. It was designed to be used in steel doors. The profile cylinder is a brilliant idea when it is fitted in a steel door, but in a uPVC door, it is a potential disaster.

In the UK, there is a massive industry based on the fitting of uPVC windows and doors. There are some very good locking mechanisms available for installation in doors and windows. But the weak point in all of these improved systems is the type of cylinder that is being fitted as standard on new doors, and available as replacements when the lock needs to be changed. The original Zeiss profile cylinder remains a design classic, but the modern equivalents are simply not good enough as they are.

What if the profile cylinder was redesigned so it was no longer the weak point on a uPVC door? The good news is that it has been. In the same way that the Zeiss cylinder became a universal design masterpiece, the ABS profile cylinder is set to revolutionise the uPVC industry.

ABS cylinders are a brilliantly effective way to stop burglars gaining entry to your property. If it is attacked, it simply closes down any access to the locking mechanism, so that potential burglars are stopped in their tracks.

More than 10 million homes in the UK have uPVC doors, and 95% of them are currently vulnerable to a force attack by an intruder. If you are concerned about the security of your door, please contact us. With ABS cylinders fitted you will be able to rest assured that you have the security you expect in your own home.

Published by PPM Locksmiths ltd in Upvc Doors • 04/07/2011 20:56:01
PPM Locksmiths Ltd 7 Dominions Arcade Queen Street Cardiff - Phone 029-20231717