New shed felt losing grit

Andymac1987

Hi all
I'm currently making an outdoor cat house, as odd as that sounds. I've bought some shed roof felt from Homebase to cut in to small shingles. Each course was tacked with felt nails and the ends stuck down with outdoor "no more nails".

It all looked great on day one, but after a few days of being outside there are random spots where the surface 'grit' has come off. Weirdly some courses are completely unaffected.

Has anyone seen this before? Do I just have a dodgy batch or could I have done something to cause this? It was a pretty big job so I'm reluctant to go and get more just for this to happen again.

Many thanks
Andy

-taff

How much cat traffic is it getting?

Andymac1987

It's not yet in commission, not finished yet.
Thanks for the response.

dunroving

Is there a tree above it, dropping something sticky onto the roof?

Andymac1987

Thanks for the response.
No unfortunately nothing above it. Bit perplexing!

greyteam1959

I would say a dodgy batch myself.
Have you still got the packaging as there may be a batch code on it ???

-taff

It may not be in commision but I assume all neighbourhood cats have access to the roof unless it's indoors?
Is it under anything they could jump on to? fence?