Alongside my house is an old coal door that was never properly sealed. Some caulk was added around the metal exterior door, and a piece of plywood nailed over the interior opening (more to keep out critters than water, I believe).
As you can see from this exterior view, there's not much I can do about removing the door itself:
But on the inside there is a cavity that could be filled in somehow:
The framing inside here was metal — it's mostly rusted out now — and there is a little bit of daylight making its way through. This is very obviously not watertight.
The house has a brick and mortar foundation. What's the right way to seal this up to keep water and critters out?
Best Answer
As you already know there is water getting into there, if you only seal up the inside to make it look better you will have water collecting between the door and your seal. You don't want a pool installed in your wall.
To do this properly you really do need to excavate the outside remove the door and metal frame (if there is a steel load bearing piece across the top I'd recommend leaving that in and if there is a rain catch on the outside that could be left, but it doesn't look like there's either from the pictures). Patch the hole with material that functionally matches the foundation wall. Water seal the patched area then once it is dry back fill where you excavated. It would be good to make that area right against the seal a little higher grade when you fill it in than the area around it to help the water drain away and reduce infiltration.