Here as in US, Canada, Eire, Scotland {& elsewhere} hard wired i/connected is the requirement for New Build Homes via local Bldg Regs/Codes/Standards.
{Plug in sort of alarm therefore won't meet the standard.}
Rarely is there a reqm't for a specific type eg Ion/Optical.
Heat Alarms are increasingly called up for Kitchens, as source of
most residential fires. {Scotlland still hasn't adopted}.
Battery interconnectable alarms are available, but hard to locate, again due to price premium.{Available via specialist electrical wholesalers}.
These are interconnected by 12V bell wire, so I know some Hsg Associations get fitted by their maintenance man as no mains voltage involved, and no Part P implications either.
They exist in Ion & Optical formats, latter more expensive and have much higher battery consumption.
These also don't meet need of the Bldg Regs & are used in retrofit only;
typically short term whilst AC hard wired programme is planned/funded.
Comments have been submitted in 2004 on the Part B consultation, as currently Regs only apply to New Build/Loft Conversions etc.
As UK has say 22m dwellings, and new house build is say 160k pa, you can see it'll take an age to make any real inroads into existing stock.
In some US Cities they get round this by making new Building Codes
retrospective
ie applies all existing dwellings say from 1/4/05.
Or
some make Reg appy to existing stock whenever tenancy or ownership
changes.
{With Part P/Home Owner Packs, that may become viable here}.
Getting existing stock within The Regs is the challenge for us all.
Its a bit quiet here lately?
The Building Regulations 1992, Approved Document B
"UK Building Regulations require all new homes to be fitted with a smoke alarm on each floor and that they should be interconnected so that detection of smoke by any one unit operates the alarm in all of them"
If its statistically proven that interconnected smoke alarms save lives and injury, are there initiatives to expand this into existing properties?
Happy New Year
Mark