Durability of expanding foam outdoors

[Ian]

I've noticed some lifted flashing at a friends house, and it appears as though a 5cmx5cm hole under the eaves has been filled with expanding foam. I've temporarily fixed the flashing with some flashband, but wondered how the expanding foam will hold up? It's in a really awkward place to repair, so I've suggested they get some mortar in there next time there is work done - but didn't think there was a big rush now.

Anyone got thoughts on the durability of expanding foam under lead flashing?

 

[Camallison]

My own experience is that it slowly deteriorates, even when covered. It may be brand dependent, or formulation, even under the same brand.

ColinA

 

[Doghouse Riley]

The above is true, I accidently sprayed a small quantity onto the side fence in the garden and it stuck like glue and I couldn't pull it off but it degraded over several months and disappeared.

 

[Ian]

Thank you both, looks like I'll suggest getting it redone pretty soon then .