Loft insulation over uninsulated cavity walls

[DIYnoon]

Hi all, need some advice re loft insulation.
The previous owners had a 2 storey extension done some time ago but didn't insulate the loft area over the top of this extension!
They had loft insulation in all the older (original) loft area which was a bit surprising.

Anyway, I need to get this done, but while I was up in the loft, I saw the original external wall which is now an internal uninsulated cavity wall and can see the gap all the way from the loft down to the floor.
My question is, should I cover over this gap with loft insulation or does it need to breathe and left open/uncovered?

Thanks

 

[noseall]

Hi all, need some advice re loft insulation.
The previous owners had a 2 storey extension done some time ago but didn't insulate the loft area over the top of this extension!
They had loft insulation in all the older (original) loft area which was a bit surprising.

Anyway, I need to get this done, but while I was up in the loft, I saw the original external wall which is now an internal uninsulated cavity wall and can see the gap all the way from the loft down to the floor.
My question is, should I cover over this gap with loft insulation or does it need to breathe and left open/uncovered?

Thanks

Cover it.

 

[DIYnoon]

Thanks mate, that's what I thought - just wanted a 2nd opinion!