Landlords: The basic smoke detection is mains battery linked smoke detectors or heat detector looking after the exit route out of a occupied building. This relates to any new house or any 2 story dwelling that is rented accomadation. 2 story being ground floor and 1st floor. the smoke detectors should be tested and a certificate issued on completion of works. You are also required to maintain the detection on a regular basis and further paper work issued on each inspection.
We have all seen and used stand alone battery smoke detectors and when the battery runs low they give a very annoying pulsed signal to bring to your attention that the battery needs replacing. How many of us have just removed the battery and left the unit not working? Well that puts us in danger straight away. The regulations were changed to tackle this problem, all new built houses are fitted with mains + battery smoke / heat detectors as part of the fabric of the building, this took care of the battery running low. The other improvement was the detectors were all linked together, if one activated, they all activated giving us time to evacuate the building.
The other alternative is, the supply and installation of a fully wire free unit / units. These link together giving you, once again, early warning in the event of a fire. The units are fitted with lithium batteries giving you a battery life of up to 10 years. These cost more to buy in the first place but are maintenance free, ( you still have to test them on a regular basis ).
You could opt for a combined intruder alarm and smoke detection system, this now gives you more options, a wire free alarm system connected to an existing telephone line, that will if activated, telephone up to 4 pre-programmed telephone numbers, telling them the type of activation, if it's a smoke detector then it will report a fire activation or a Co2 detector will report a gas activation, how good is that? The unit is also an intruder alarm and will also give an audible warning within the protected premises regardless of the type of activation.