I am loking for pointers to any good decisions on membership of the same household.

The context is an application for help with housing costs which was refused because the client was a member of the same household as the landlord who is a close relative (sister & sister-in-law).

Can anyone help with any good suggestions for case law I can quote when considering if thier decision is JRable?

You could try Kerr v Department for Social Development <2004> UKHL 23

As a House of Lords decision, it seems like a good decision, and in terms of UK law, about as high as you can get...

I have it, but have not yet read it in full, but it seems to meet some of your criteria....

Not sure if it is on Rightsnet or freely available elsewhere, as have not needed to search for it, but if it isn't to hand, post back, and I'll e-mail to Shawn for publication...

http://www.parliament.the-stationery-office.co.uk/pa/ld200304/ldjudgmt/jd040506/kerr-1.htm

I don't know of any binding decisions on this specific point,but if you can get hold of an old "S" Manual, you'll find a section on "same household".
Regards

R(SB)4/83 is pretty good. Its on rightsnet.

If I knew how to, I'd have done you a link.

Here's the link to R(SB) 4/83 -

http://www.rightsnet.org.uk/pdfs/rsb/4_83.pdf