I have a brick loadbearing wall that runs down the center of my house in
crawlspace. The bottom of the wall sits on the dirt crawlspace
footer). I have dug out the dirt under a small portion
(approximately 2 feet
long) and several feet deep. I poured a large
footer (with rebar
re-enforcement) and plan to build up a cinderblock
column underneath the brick
wall to support it from beneath in that
spot. I will stack up the concrete
block and fill, my question is: is
there anyway to get a little pre-load under
the brick. Ideally i would
jack up the house a 1/4" or so at that point and
slide the block in so
it fits tightly then let it back down on top of it. I
don't think I can
do this though because I don't think i can jack up the old
from beneath (it might fail with that much pressure in one spot).
What would be ideal is if there were some type of artificial steel
contraption with adjustment screws that I could put in the
column and put a few
turns of the screw when i was finished building it
to tighten it up (kind of
like an adjustable lally column, only it could
be placed in a cinderblock column.
Build a temporary wall alongside the brick, to hold up the (still
overlapping) joists, using about a 4-5 foot piece of steel, a couple of
house-mover bottle jacks, and some steel plates on the dirt to set the
jacks on. Maybe some cribbing if the jacks are not tall enough. A house
moving company, or rental house that deals with the trade, will have
this all in their yard. Just build the wall up underneath the brick as
tight as you can, and use shims above the brick as needed to make the
floor above level.
By the way, if you were adding footer under this section to catch a
point load above (rather than just a sagging floor), you probably want
to look at replacing that part of the brick with new concrete block, all
the way up to the load, with a piece of PT or steel on top to catch and
spread the weight. Old brick that has been undermined sometimes likes to
crumble unexpectedly, or the mortar bond in that area lets go.
Just for giggles, may want to ask a house moving company, or their usual
foundation company, for a price on the proper cure, if there is access
from one end. To wit, support the whole run on jacks and cribbing, demo
the brick, and replace with a steel beam on proper piers and footers
every 8 feet or so. If they can get a straight shot at it, they can
slide a beam in through a hole barely any bigger than it is.
Hard to give reliable suggestions, since we can't see the bottom of your
house from here...
If you just want to make sure it's a snug fit between the new supports
and the bricks, expanding concrete might work.
Build up the wall with concrete blocks to within x inches of the brick.
Top off with x inches of expanding concrete.
I have no idea what 'x' should be, how much aluminum to add to the mix,
nor what the forms need to look like. I'd sure want to run the plan by
an experienced mason before I tried it.
If you search for aluminum powder and concrete you should get on the
I used a cheap 10 ton bottle jack to do raise the house and fit in
lally columns. Used proper 1/2" steel plate chunks from local scrap
yard under the joists, sills. House mover gear though, is good if you
are doing a whole lot of supports at one time.
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.