Hole in exterior wall - advice needed!

[NickSpam]

Hi there

We recently bought a house and I've been trying to get to the bottom of why it's so draughty.

I've found a couple of holes at the bottom of the wall where an extension joins the house - I've attached a photo of one of them. This is about 6" wide and is where a flexible water pipe (attached to an outdoor tap) comes out and goes quite a way under the wall.

Not being an expert it looks to me like it might be poor workmanship. The obvious (easy) solution presumably would be to put some expanding foam in there however before I did so I wanted to check if anyone could recommend any other options (unless of course that's the best one?).

Any help would be gratefully received!

Many thanks!

 

[Burnerman]

I'd scoop that gravel away and fill the hole with a sand and cement mix, personally - sticking a bit of broken brick in first just to give the compo something to grab to.
Expanding foam is all very well but usually isn't UV stable and can be pecked away by birds.
John

 

[NickSpam]

Thank you very much John! That's really helpful!