What's fallen off my roof and what do I need to repair it?

[Potatan]

A chunk of render (?) fell off the side of the roof on my single storey extension last week. See attached pics.

How should I approach fixing this? It looks like I should be able to just trowel something back on after maybe brushing loose material away.

I'm trying to avoid buying a sack of something, or even perhaps two sacks just to mix up a small amount. Is there something I can get that's ready-mixed and in a tub? Any other tips?

Thanks

 

[Mottie]

Just get a tub of ready mixed mortar from B&Q. About a tenner.

 

[^woody^]

Buy a few sacks and repair the whole lot.

 

[Potatan]

ready mixed mortar

Exactly the info I was looking for, thanks