loft insulation over exisiting loft boarding

[cameron]

I have a large loft which has approx 70mm of glasswool insulation throughout. This then has chipboard flooring laid on top, again throughout.

My question is....Can I put additional insulation say about 200mm thick directly on top of the chipboard or do I really take up all the chipboard!!!!!?????

Cheers

[welsh brickie]

you need to take up the chipboard.