Loft Insulation Advice

[annd]

Looking for some advice please...

We've had a number of guys come look at our loft, some have told us we need to replace existing insulation because it's all mouldy, other have said it's totally fine to lay additional insulation on top as it's in good condition. I'm very confused. It's got some black stuff on it, but not sure if it's mould as it feels dry.

The same was said about the boarding on the rafters. Some said it was sufficiently ventilated and can stay, others said it's no good and should go!

Any thoughts / advice greatly appreciated!

 

[Wayners]

Any smell to it?

 

[annd]

No smell I don't think

 

[Wayners]

Reason I asked was mice turn loft insulation that colour and it smells musty. I don't know why that's gone like that tbh. I don't think its mould