Update 2 October 2018: Spider-friendly sensors (yes, really!) have now been fitted and seem to have solved the problem. Thank you for your patience. Hopefully this will be the last of this particular problem.

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We're aware that our building alarm has been triggered overnight on several occasions recently, causing disturbance to local residents and neighbours. Our sincere apologies for this; we do not wish to be a nuisance. 

The system has no faults; the cause has been identified as an explosion in the spider population crawling over the external sensors, triggering the alarm. We're working with our providers to find a solution. 

Thank you for your patience; we want this to be resolved as quickly as you do.