Thats why I didn't tell you about insulated tile backer boards..............people don't like to pay out for the extra cost of them lol.

TBH if its going to get done its worth doing it properly, just amazed at how much they are

If you have a timber sub floor in the conservatory, then lux boards can be screwed down with stainless steel screws and washers.

If it is concrete then as Rookery has said, you will need 3 bags of adhesive as they need bedding down.

My 3 bags were just for the tiles. In my experience, I get about 4 mtrs out of a bag with that trowel allowing for a bit of bedding up in places. The insulation boards are worth it in the long run as the heating will be more efficient and more cost effective. You can get Fastwarm 1250 x 600 x 10 insulation boards on line for £7.00 and you will need 16 minimum.

Any clues as to where to source them? Still not been to anywhere to price this up. My better half neglected to mention the bed is arriving next friday, so I need to have the room decorated & carpet down by then. Wooooo!

As you're in Manchester you could get everything you need from Ceramic Tile Distributors (CTD) in Denton, or their Warrington branch if thats more convenient. They stock adhesives etc by BAL, Mapei, Weber and more besides. I think you'll find Weber the cheapest. They will sell you the UFH and insulation boards too and any tools you need. If you give them the whole order, they'll probably do you a good deal and also deliver too. Tell them what you want and ask for a good discount for giving them the whole order. PM me if you want me to spec it up for you.

Cheers,
When I have the readies for it I'll drop you a mail, dare say it will be easier to negotiate if I look like I know what I'm talking about!