DIY Doctor UK DIY Forums

As I need to put rock wool insulation in a new ceiling in the room below a loft conversion could anyone tell me please if it is sufficient to run the cabling in the space between the insulation and the floor above.

As the joists are engineered timber of 12inches in height and the insulation is only 50mm in depth there appears to be plenty of room to ensure that the cables aren't touching it.

Also should the cabling be on the ceiling side or the floor (above) side of the insulation please? Given the depth of the joists is it right that the cabling won't need to be put in conduit?

Thanks for any help.

Cable should be 50mm from either top or bottom surface to avoid any nails etc used in the future. When correctly cleated to beams the beams themselves will help remove the heat the regulations tell us a 2.5mm sq cable fitted to Reference Method 100# (above a plasterboard ceiling covered by thermal insulation not exceeding 100 mm in thickness) is rated at 21 amps and the limit for cable used in a ring final is 20 amps so it is within the limit by 1 amp.

http://www.doncastercables.com/technical-help/4 shows the tables but can't find any of the pictures on line.

Thanks Eric for your response which is v helpful.

Regards