I noticed this before, and now have a mind to do something about it:

There are a number of pilings in the interior foundation of my 98 year
old 2 story 1925 square foot house. One of them doesn't reach the base
and is suspended above it by about an inch. There's an interior door
downstairs that has been giving me problems. Occasionally, it won't
close and I sand off some of the top of the door with my belt sander. I
did that around 2 months ago and lately, the door is sticking again.
WTF. Well, I surmised that this door just might be close to the
suspended piling, and going under the house a few days ago, sure enough,
that piling is right under that door!

So, I figure I should lift up the house a bit with house jacks just on
either side of the piling and slip a solid piece of hardwood between the
bottom of the piling and the top of the base. Then lower the jacks so
the piling is taking some weight. How much weight, I guess I can't
really determine, but hopefully somewhere not far off from what it
should be supporting.

I borrowed a couple of 20 ton house jacks from my local tool lending
library and the guy said I should probably dig out the old piling base
and pour a more substantial one, maybe 2+ feet square. He said the
piling has sunk because of puddling in the past. I said, if what I'm
doing doesn't work I can always do that and borrowed the jacks anyway. I
don't believe that any puddling has happened under there for decades.

I'm wondering just how much I want to lift the beam running above that
piling before slipping in a board. The guy said I'll start to hear
creaking/groaning from the wood and I can determine from that just how
much to crank the jacks. I'm wondering if I should think in terms of
raising the beam, say, 1/4 inch before shoving the shim-board
underneath.

Dan

wrote:
....
I'm wondering just how much I want to lift the beam running above that
piling before slipping in a board. ...

Start by figuring out how low it is compared to level.

Generally, you can figure on a half-inch on a lift if it's that far out
w/o much problem. Much more than that at a time will probably start to
pop sheetrock/plaster, move window frames, etc.

But, if it's settled that much previously, you should also see signs of
that in window casings are out of square, etc., too. If so, you'll
begin to square them back up as well.

I'd go w/ the amount to get the door swinging freely at the initial and
judge from there.

On the additional support--it's got to have settled for a reason.

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