As of the 1st October new fire regulations stated that, all holiday homes should have thumb turn cylinder locks fitted to all external doors.
Exit doors, such as the front or back door, should always be easy to unlock and must not need a key to unlock them from the inside. A simple latch or thumb turn is usually good enough. However, you may need to consider whether all guests are able to open these doors. A simple single action turn handle or lever will often be more appropriate.
Note this says fire safety law and therefore is the legal requirement of all landlords, certainly for those with holiday lets.
An example of a lock with a thumb turn on the inside is a thumb turn euro cylinder.
On all upvc type doors, this is simply a matter of changing the cylinder. On doors with mortice (often called ‘Chubb’ type) locks, you will need to change the lock, handles and purchase a cylinder. While thumb turns are great for fire escapes, they do pose a security risk as it is possible with certain tools to go in through the letterbox and rotate the thumb turn to gain access. Therefore any locks with thumb turns on a door with a letter plate, should also purchase a letter plate guard to alleviate this problem.
This is essential to make sure no one can lock a door, remove the key and be unable to get out if a fire breaks out.
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