The wall of my house has what looks like a hole in the brickwork and seems to have caused damp and water damage inside the property. I think to fix this I need to replace the damaged brick and apply lime mortar.
I've only just brought the property so don't know the full history of the issue (I suspect it has been like this for a while) but want to get it fixed ASAP so I can start work on the internals of the house without the risk of further water damage. My concern is that as the house is Victorian it has lime mortar and repairing this now as temperatures drop to below 5C might create issues with the mortar freezing before it has fully set. I'm told that I should really wait until spring if using lime mortar.
I believe I need to avoid using anything with cement in it as this isn't breathable (photo shows a previous repair that has failed with what looks like cement).
My question is whether there is a way to repair this correctly in cold conditions and if not and I have to wait until spring is there a temporary repair I can do to prevent water getting in? Someone suggested expanding foam but I'm not sure this is a good idea.
Images attached both external and internal, The internal is the ceiling on the ground floor below the hole. The damaged brick is to the left of the window sill. The brickwork around the boiler flue and overflow pipe has gaps too and needs repair.
Thanks