what size fire extinguisher is recommended for households

Usually at least 1kg, preferably 2l/2kg.

ABC Powder is the traditional go to as it's cheap, yet is still powerful compare with other agents mass for and is (almost) multipurpose. However it is messy and can damage surfaces and equipment (especially if warm or hot) and isn't pleasant to inhale. It's also ineffective on cooking oil fires.

A more expensive but handy alternative is water mist, which is non damaging and effective on the main domestic fires of solids materials, electrical equipment and cooking oils

 

https://www.safelincs.co.uk/1kg-abc-dry-powder-fire-extinguisher-ultrafire

https://www.safelincs.co.uk/2kg-abc-dry-powder-fire-extinguisher-ultrafire/

https://www.safelincs.co.uk/britannia-2kg-powder/

https://www.safelincs.co.uk/1-litre-water-mist-fire-extinguisher-ultrafire/

https://www.safelincs.co.uk/britannia-p50-2ltr-water-mist/

 

I must agree with Anthony, although drypowder is good for most things (Except chip fryer fires) and it is cheap to purchase, once you use one, (indoors) you soon wish you hadn't. They do make a lot of mess, and considerably reduce visibility, I would suggest not one, but two 1 litre water mist extinguishers, that way you will always have one for spare, and when being used, clean up really is very simple (Because it really is de-ionised water)

If you do not know, once a fire extinguisher has "been started" you can stop the discharge, but you can't then "put it back" for the next time, it will lose its pressure within a short time.

I would also suggest you check your smoke alarms regularly, and if you haven't got any Click here