Historical Hospitals near Caerphilly

[rvb]

I am trying to find images of historical hospitals around the caerphilly area.  My grandparents lived in senghenydd, Glamorganshire at this time.  I have recently received this picture attached.  It shows my grandmother and a group of ladies all wearing slippers. I believe it is a hospital or convalescent place.  I thought at first it was caerphilly miners hospital but I am told it is not. The picture was taken approx 1940's.  I have googled it over several hours and cant find anything that looks similar in architect to caerphilly miners hospital.  Does anyone have any suggestions?  thank you