My loft conversion company weren't keen on boarding the eaves so I'd planned to do it myself, using loft legs to create an air gap between the insulation and the boards. I've opened up the eaves hatch expecting to see a tidy clean layer of insulation (300mm was specified by the architect) and have found a jumbled mess of old insulation and building debris. In some areas it's piled fairly high and in others it barely covers the surface.
My understanding is that old insulation can be retained, although I thought it was customary to put new material on top to create an even layer that would be more pleasant to work with. I'm now undecided about what to do next.
Would you advise laying boards above this as it is, or asking the loft conversion company to come back, tidy up and put another layer above it - or even replace it? The house is approximately 60 years old but I don't know how old the insulation is or how to tell if it's still useful. It's pretty filthy and has had rat poison scattered on it in the past.