I have a 30's semi detached property with about 100mm insulation between joists. Areas of the roof are boarded (chipboard) and carpeted by a previous owner. I can't get the loft boards out due to a combination of the old carpet and the poor condition of some screw heads. So just rolling insulation over the top of everything would be the easiest solution to meet current insulation depth requirements, it'd also reduce the amount of disruption in the loft, which is a bonus due to the delicate lath and plaster ceilings below. So in summary, is it acceptable under regulations to loose-lay insulation over boarded areas? FYI There is no plumbing or water tank in loft and the property has been newly re-wired by an NICEIC electrician, so I assume he has ducted the wires under the boards correctly etc.
How deep are the joists? I would image not that deep for a 30s house so the insulation may be squished with the flooring right on top. If so, I don't think that would cause a condensation problem. However I'd be very tempted to take the boards up and do a proper job even though it might be difficult to do.
Thanks for the replies, maybe i'll have another go at getting the boards out, or maybe ill just play it safe and lay the insulation over the top. see how brave im feeling (just had ceilings skimmed)