I've had two B&Q 50W halogen downlighters installed in my bathroom ceiling, just below the loft. I see that the spark who did the job has peeled the insulation away from the fitting that sticks up into the loft so that it's bare for about 500cm all around. Is that margin of safety really necessary? I seem to remember that there is some other way of fireproofing these lights without destroying the integrity of the loft insulation.