I have seen adverts on TV regarding this and looking for JBK knowledge on people who have already actioned this. Particularly product advice, cost effective, ease of install, where to buy, etc. In short you now need at least one smoke alarm in main passageways (downstairs hallway, upstairs landing) main area (lounge) and a heat alarm in the kitchen. But critically all have to be interlinked.   In my case, i need 3 new smoke alrms and a heat alarm. This should be fai