Closing off/plugging a chimney. DIY options that should meet code?

In My Humble Opinion
1

Disclaimer, I know code varies by local.

We bought the house at the end of December 2020. We replaced the Water Heater 2 months ago. The chimney is no longer in use. The Air Handler and Water Heater both exhaust outside via PPC pipes. (all done professionally)

I need to repair the mortar which should be fairly easy, but I also need to plug the open hole. I was thinking about just placing a paving block or piece of slate over the top and mortaring it into place.

Is that a fix that would meet most codes? Do I need to somehow build a plug like the prior owners had done for the furnace?

Click Pic to expand

2

I have no clue what your local building code says, but I’d be surprised if the rules are onerous. There are rightly lots of rules about how working chimneys should be constructed, but “ornamental things that look like chimneys, because they used to be chimneys” strike me as less likely to have accrued a lot of rules.

That being said, I’d want to seal it pretty thoroughly, to keep out both weather and animals.

3

That sounds pretty sound. I’ll stick to my paving stone or piece of slate idea probably.

4

No longer used Chimney is covered and repaired.

5

Looks good!