Roof Space problem

[bulittooth]

Hello
I am trying to help my sister out at the moment with her roof space. The backs of tiles appear to have an old sealant? that is dry and crumbling, with the tiles full of condensation. her insulation is all damp and all the bedrooms below are now moldy. - Will scraping off this crumbly sealant and spraying tiles with polyurethene foam work and stop mold in bedrooms?
Thanks

 

[big-all]

heeelllooo and welcome bulittooth

do not touch the tiles check there is ventilation by special tile vents or make shure the loft insulation dosnt block the eaves
it should feel cold and draughty up there with the trap door shut

also there should be no extraction from the house into the roof space unless its sealed and exits through the roof or soffits

 

[Chukka63]

ditto,check the roof has some ventilation and that its not blocked/covered.if there isnt any,get some,various methods.if the insulation is blocking it,just remove the blocked areas

 

[bulittooth]

Thanks for the advice - just to double check - the crumbling on the back of the tiles - is this old sealant?
Thanks again
Alex

 

[r896neo]

probably some bitumen sealant or similar, but as mentioned you want to create a layer of insulation above the bedroom ceilings/ floor of attic space and then have a cold draughty loft space above it. You do not want to insulate the underside of the rafters unless you are converting the attic into habitable space.

 

[bulittooth]

Many Thanks - will get started cleaning up the mold tomorrow!