Chimney detaching from wall

[rbaake]

How would you report this?

Single family home built in 1937. Free standing single flue chimney venting gas fired appliances only. Fiber cement shingles (date ?), installed as far behind stack as I could see. Obviously, this has been like this for along time.

House in costal NJ town and built on sandy soil (very little settling in block foundation BTW).

Second photo is noting the vines but shows the stack well.

Download Attachment: Photo 03.jpg

96.95 KB

Download Attachment: Photo 3.jpg

95.35 KB

[Tom Raymond]

Look at your first pic again. You can clearly see in the mortar that the siding was there before the chimney. It's tipping over, and will continue to move until it's strapped to the wall or is laying on the ground. I'd tell 'em to fix it sooner rather than later.

BTW, the fiber in those shingles is asbestos, and they are likely original. http://www.customtileroofing.com/Tiles- ... llery4.asp

[Jim Katen]

Look at your first pic again. You can clearly see in the mortar that the siding was there before the chimney. It's tipping over, and will continue to move until it's strapped to the wall or is laying on the ground. I'd tell 'em to fix it sooner rather than later. . . .

I disagree. It might well be perfectly stable at this point. Chimneys often do this when they were placed on topsoil, organic material, or inadequately compacted fill. If that's the total movement that the chimney has experienced in 70+ years, it's not a foregone conclusion that it will continue to move till it tips over.

This is one condition where the most sensible thing to do is to carefully monitor the movement.

If there are signs that its still moving, the solution is to underpin the foundation. Adding straps will not stop the foundation from settling and it'll probably cause the chimney to crack.

[Tom Corrigan]

The chimney was built subsequent to the original construction. This means that the inboard portion of the chimney was placed on top of the protruding lip of the original footing. The remaining (outboard) portion of the chimney was supported by a new footing.

The new footing settled slightly (as did the original footing during the first several years). This settlement caused the chimney to move away from the building. This movement is sometimes limited by brick ties installed between the chimney and the sidewall.

If movement is found to be continuing, it is possible to have a larger footing installed under the "new" footing. This will reduce unit loading of the soil.

So yes, it is a defect and it may need to be fixed.

Tom Corrigan ret.

[Marc]

Is the roof/chimney flashing still functioning? Apart from any instability issues, I'd be concerned about rainwater/debris becoming trapped between the chimney and the exterior wall.

Marc

[Jim Morrison]

I couldn't tell you how many of the cheap-ass 'L' brackets used to hold the chimney to the house have rusted out and failed in my experience. This is a very good time to punt.

[rbaake]

Great comments thanks for your time.

For some reason, I generally avoid telling people to "monitor" things, especially when its been in service for as long as this. However, I agree it may be appropriate in this case.

[mgbinspect]

Tom C and Jim K have nailed this one down pretty well. I always poured a spread footing, for add-on chimneys, that was much bigger than required to markedly reduce the possibility of settlement like this.