Chimney Re-pointing Alternatives

15 years ago

The chimney in my house (1911) runs behind walls and is not exposed, and therefore doesn't add to the aesthetic of our house in any way. It simply acts as a flue for the furnace and water heater.

Our second story and attic is gutted and we've noticed that the mortar could stand to be re-pointed within 10 feet of the roof. One of the sides of the chimney runs up an exterior wall, and is nearly inaccessible. When we put our walls back up, the chimney will not be visible. Instead of going through the trouble of re-pointing, I'm considering two other options:

1. Coating the entire chimney with a layer of mortar, gaps and brick faces.

2. Apply foam to the existing gaps and/or cracks.

For the side we can't access, that would have to be foamed regardless.

Does anyone have thoughts or past experiences with either of these two options?

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Comments (7)

hendricus
15 years ago
2. Don't use foam on a chimney, only cement or mortar. Stuff that wont burn if you have a chimney fire.
brody_d
Original Author
15 years ago
Good point, and the more I think about it, I imagine heating foam would produce some unenjoyable toxic fumes.

I still have the one side that inaccessible. I can reach an arm back there, but doubt I'd have the room to maneuver a tool of any sort.

Would fire blocking foam be appropriate?
kframe19
15 years ago
If you're worried, your best bet would be to have a chimney liner installed.
brody_d
Original Author
15 years ago
Weather and time finally cooperated and I made it up on the roof to inspect the chimney. From in the basement I could tell there was a terracota liner, but not what condition it was in. From above, the terracota was definitely chipping away, and could have looked better. There was also, clearly visible, fiberglass insulation coming out of a crack. It had been stuffed into a crack, 6 feet down from the top, in one of the difficult to access areas.

From what I saw, I think it's obvious that a chimney liner will need to go in. That'll be easy enough to do.

Let's say I add the liner, cap, etc. The areas that need to be repointed have obviously been damaged by water intrusion from the room. If I protect the outer surface of the chimney which is inside the house from further degradation, should I expect the mortar to weaken further?

If further weakening is not a concern, should I even bother repointing anything other than a major trouble spot (i.e., holes and cracks stuffed with fiberglass)..?
lucy
15 years ago
Won't your local fire dept. do an inspection for you? I had mine done for nothing, and would not have dared to use my own eyeballing as expertise re the state of the chimney or anything connected with it.
kathleenca
15 years ago
It seems you need to have the chimney inspected by a fireplace cleaning/inspection company to determine what really needs to be done. There's no sense in guessing when a wrong guess could end up in a house fire.

Kathleen
brickeyee
15 years ago
"Won't your local fire dept. do an inspection for you?"

Unless they run a camera down the flue they are not really doing a very good inspection.

Find a chimney sweep with camera gear and have it checked.