Here in the U.S., one can buy two different types of what we would call recessed lighting. One is "No Insulation Contact" whose "can" or top part is a single thickness of aluminum into which the bulb, usually halogen, fits. It has an extension which serves as a code approved junction box and contains the wires that have been fitted together with wire nuts. The other type is "Insulation Contact" (IC) and consists of about the same cnstruction with the exception that the can into which the bulb fits is double walled and already insulated. It also has the junction box attached. I've used both kinds during remodeling projuects. The non-insulated type works well in, say basement cielings where there's no insulation, while the other works well in the aoolication you describe. I can't beleive they don't also have them in the U.K. The insulation contact type ar emore expensive, but not prohibitevely so... Best of luck! (Here's a link describing the fixture:
http://www.doityourself.com/stry/installrecess light )