will cardboard boxes insulate my loft?

[sylar]

And if so will they be better flattened or made up. I have 40 large flat packed boxes!

They will provide some insulation, but they won't conform to fire standards that more conventional insulation does. I doubt that their insulative properties will be as good cm for cm than the regular stuff either. I suspect that flatened would work best, unless they are extremely thin boxes (less than around 3" tall).

there are many cheap insulation offers around at this time of year, just keep an eye out for them. As examples npower were offering it for a pound a roll to first 10,000 customers. Homebase had buy 1 get 3 free. No idea if either have any left.

have just learnt focus have a buy one get 3 free offer Space Combi Loft Roll Insulation 100mmx12m finishing today. Might have to phone and see if they had any left.

apparently B&Q also have an offer on insulation if you missed the focus one.

Thanks both. We have loads of insulation I'm just trying to put the boxes to good use and wondered whether they'd insulate it any more.

Untreated cardboard is a fire, mould and vermin risk.Why not use the cardboard as logs for the fire?