A point brought up in this thread was that expensive AFDDs being mandatory in flats in blocks of 6 floors and over, installation will be cut to the bare bone to save costs, with 1940s/50s levels of scant circuits. They may filter down to all residential installations. But it can be done safely and cheaply...
So let's look at a 3 bed flat on the 6th floor.
1. One final ring with a 32A AFDD. This has no heavy current appliances apart from say a 3kW kettle. Most being TVs and the likes.
2. RCBOs on all other circuits.
3. LED lighting, smoke alarm and bathroom extractor fan has one circuit using 1.00mm cable. 3A RCBO.
4. Heavy kitchen appliances on one circuit. A 4mm cable to a bank of FCUs in the kitchen. 1.5mm cable from FCU to each appliance: w/machine, tumble dryer, dish washer. Appliances hard wired in - safer. 40A RCBO.
5. 6mm cooker cable to the oven and induction hob - no need to be on separate circuits. Both hard wired in. 40A RCBO.
So, four circuits. One AFDD and three RCBOs. 1.00mm and 1.5mm cable used. Cheap and safe.
The same could be for an average British semi. Maybe with two lighting circuits - but two are not required. This gives five circuits. Installation costs are then cut right down.
So let's look at a 3 bed flat on the 6th floor.
1. One final ring with a 32A AFDD. This has no heavy current appliances apart from say a 3kW kettle. Most being TVs and the likes.
2. RCBOs on all other circuits.
3. LED lighting, smoke alarm and bathroom extractor fan has one circuit using 1.00mm cable. 3A RCBO.
4. Heavy kitchen appliances on one circuit. A 4mm cable to a bank of FCUs in the kitchen. 1.5mm cable from FCU to each appliance: w/machine, tumble dryer, dish washer. Appliances hard wired in - safer. 40A RCBO.
5. 6mm cooker cable to the oven and induction hob - no need to be on separate circuits. Both hard wired in. 40A RCBO.
So, four circuits. One AFDD and three RCBOs. 1.00mm and 1.5mm cable used. Cheap and safe.
The same could be for an average British semi. Maybe with two lighting circuits - but two are not required. This gives five circuits. Installation costs are then cut right down.