"I recently bought my first house here in Seattle. It is old, 1941,
has had a few extensions and modifications done to it through out the
years. One of these modifications is a extension to the house that is
on a slab extending out from the foundation. There is a section in the
wood flooring that is high centered where it crosses over the
foundation and onto the slab section of the house. You can see it
clearly in both rooms that are extended onto the slab. There are also
cracks (that someone has attempted to fix) in the wall and ceiling.
One of the first projects I was going to do is refinish the hardwood
floors in both of these rooms. I am worried that finishing the floors
first is putting the cart before the horse and I will end up wasting
the 20 hours or so it will take me to refinish them if I am later
required to somehow repair the slab (mud-jack?).
My questions are:
1. If the extension is 10+ years old (looks at least that old) is
there much of a chance that it is still settling?
2. If it is done moving, could I just re-level the inside of the
3. Would getting the extension "mud-jacked" required ripping up the
hardwood floors to get down to the slab and drill holes?
4. Does it make sense to use a non-poly based finish for the floors
(like waterloxx?) so that I can spot-refinish the floor if the slab is
Thanks in advance for any advice!
Did you have an inspection done before you bought the house? The
inspection report should have given you some insight into what is going
on. It's impossible to diagnose this type of thing without seeing it
and figuring out how it was built and what is going on. If it was
not built correctly, the slab could certainly continue to sink/crack
more, even though it's 10 years old. As for cracks in the ceiling and
walls, some small cracks are going to occur in most structures from
shrinking/contracting, slight settlement, etc. These aren't structural
issues. However if the cracks are wide and continuing to expand, or
doors/windows are going out of square, that's a very different story.
Before I did anything, I'd get an expert opinion from a structural
Sure it might settle for 5-500 years. Get an engineer out. Who can
answer not knowing soil, subsoil, water table , foundations-footings on
slab and house etc etc.
2 different foundations should have never been done.
- posted on April 7, 2005, 4:22 pm
Yes, I did have an inspection done before I purchased the house. The
engineer seemed very competent though he did not even mention that it
is on a slab. I think it may have been a mistake on his part, as I did
not realize that there was an extension until I measured the floor
upstairs and then the basement. Now that I think about it, it might be
a crawl space, not a slab. I will have to try and poke around more
outside the house (its hard to access that side of the house outside).
All I know is that there is an obvious change in the concrete where the
extension foundation spaces meets the original foundation. There is a
small crack noticible outside, but its pretty small, 4-5 mm maybe.
Maybe I can convince him to come out and look at it for free since he
missed it in his original report.
Thanks for the advice!