Are you or your customers frustrated with doors that are difficult to operate and unlock ? Are you making costly site visits to address issues caused by thermal expansion ? If you want to eliminate unnecessary service calls for sticky locks , keeps and hinge adjustments while saving time and money , as well as boosting your sales and brand reputation , then AV4 is the solution to smooth operation in the face of thermal expansion . A known industry issue , thermal expansion is a natural phenomenon where materials expand when they are heated , and contract when they cool down . This occurs because heat causes the atoms in the material to vibrate more vigorously , which in turn makes them occupy more space . Thermal expansion can have practical implications on the functionality of all door materials , affecting fit , operation and durability over time .

Adapting to misalignment

As a door naturally moves , more force is required to engage the locking mechanism , as the parts no longer align . This means that extra pressure needs to be applied to turn the key , effecting use and functionality for the doorset and triggering call outs for the installer to investigate . However , AV4 has been designed to address these challenges . With wider installation tolerances built into the lock , AV4 requires up to 70 % lower force to operate than competitor auto locks and auto-engaging locking solutions . George Smith , Technical Manager for Winkhaus UK , explains how AV4 is tested , the results , and the benefits this has for the fenestration industry .

George said : “ The force required to retract a locking mechanism can be affected by many factors including the quality of installation , alignment of keeps and door maintenance , temperature and building structure . As these factors fluctuate , so

does the potential deviation of a door , necessitating meticulous testing against a stepped increase in tolerance to simulate real-world conditions .

“ This imperative assessment aligns with PAS24 , the robust security standard governing doorsets and windows , drawing its testing methodology from BS6375-2 . Mandating a maximum force of 2Nm for retracting the locking mechanism , with lower force indicating smoother operation , underscores the commitment to fortified security and reliability .”

Testing against real world conditions

Winkhaus wanted to measure the real-world impact that AV4 can have on a doors ease of use , and invited end-users to test how it operated under thermal expansion compared to other locks on the market .

When it comes to thermal expansion , the industry standard tolerance for doors is up to 5mm with a tolerance of + or-2mm being commonplace . To simulate deviation , packers were inserted in 2mm increments with initial measurements being take from zero deviation . The doors used were from the same fabricator and were formed on the same date and batch of manufacture . For the testing we benchmarked AV4 against the AV2 , the current market leading autoLocking solution and a range of competitors products .

To start the test , we measured the force required to operate without any packers installed , so zero deviation in the doors used . We expected to see little difference but found that not to be the case with AV4 requiring under 70 % less force to operate .

All the locking solutions tested met the PAS24 requirement , operating under the required 2Nm force to operate with 4mm packers installed at the top and the bottom of the door . AV4 at this stage required between 36 % and 47 % less force to operate than the other products tested . Above this point there was a high failure rate with the competitor products tested , and we did not continue testing if locks required more than 2Nm force to operate . AV4 at this point of the testing was only requiring 0.75Nm force , so we continued to increase the number of packers , and therefore deviation of the door .

Beyond 4mm deviation only AV2 and AV4 still operated below 2Nm in the sample of products we tested . At 6mm AV4 continued to operate , and again with 8mm

of packers installed – double the industry standard and tolerance for door manufacturers . At 8mm AV4 required only 1.54Nm of force to operate , lower than any other lock we have tested , whilst remaining easy to operate from either key or thumbturn .

Enhanced user experience

AV4 offers significant advantages for fabricators and installers , as it is able to work in situations where other locks might not perform due to its low force to operate . Not only does this reliable locking solution reduce the need for costly replacements over time , but it also minimises the lost time and expense associated with frequent maintenance visits , enhancing the reputation and profitability of fabricators and installers within the industry .

For homeowners , the AV4 offers user-friendly operation , ensuring ease of use for individuals of all ages and abilities . Its low force to operate allows accessibility to everyone , including those with disabilities that affect their ability to grip or apply force to other locking solutions . Additionally , the longevity and reliability of AV4 means that occupants can enjoy the convenience of a single , dependable locking solution throughout their tenure - from children to grandparents - promoting a sense of continuity and supporting the requirements of the future home ’ s initiative .

www . winkhaus . co . uk