Hi. I'm planning to extend the letter slot on my flat front door as it's currently too small for almost anything to fit through. The flat building was built in about 1900. The front door has what seems to be a fireproof panel attached to the inside, which is painted, and I'm worried that it might be AIB, so I'm wary of going at it with the jigsaw. Is it likely that it is AIB, and if so, should I just leave well alone?
Thanks in advance for any help.
Thanks in advance for any help.