I don't know whether this is an appropriate question for this NG, but I
don't know where else to post it. If someone has a better recommendation,
I will be happy to take it there.

I have a suspicion that tree roots are stressing the foundation of my
house. However, the symptoms are not constant -- they vary with the time
of year.

My question: In general, do tree roots grow at different rates during
different seasons of the year?

Thank you very much for any thoughts.

David wrote:
I don't know whether this is an appropriate question for this NG, but I
don't know where else to post it. If someone has a better recommendation,
I will be happy to take it there.

I have a suspicion that tree roots are stressing the foundation of my
house. However, the symptoms are not constant -- they vary with the time
of year.

My question: In general, do tree roots grow at different rates during
different seasons of the year?

Thank you very much for any thoughts.

They would have to be mighty big roots to stress a house foundation. Is
the house on a standard slab, a chain wall, or piers? Most common cause
for slab cracking, at least along the Gulf Coast is that the house is
built on a clay layer, doesn't matter if the clay layer is down three or
four feet. Clay shrinks in dry seasons and swells in wet seasons. Nearly
every house I have owned in 45 years along the coast in Texas and
Louisiana has, of necessity, been built on top soil covering a clay
layer, all have ended up with slab cracks, from small, no consequence
ones, to the ceiling cracking along with the slab.

Check around your house and see what is doing the job.

George

The message
from David contains these words:

I don't know whether this is an appropriate question for this NG, but I
don't know where else to post it. If someone has a better recommendation,
I will be happy to take it there.

I have a suspicion that tree roots are stressing the foundation of my
house. However, the symptoms are not constant -- they vary with the time
of year.

My question: In general, do tree roots grow at different rates during
different seasons of the year?

No, but they have a different effect on soils and foundations at
different times of the year, which fits your symptoms.

For instance, in winter a deciduous tree has shed its leaves, and
therefore its roots suck a lot less water from the ground. In summer,
the same tree is covered in leaves and making new growth above ground;
so it requires a lot more water. When it sucks a lot of water out of the
soil, the soil is drier, and shrinks. Soil shrinkage around foundations
can cause the building to move and settlle, showing cracks at stress
points.

After the foundations have moved slightly in dry soil, if clay soil
is suddenly re-wetted (by heavy rain in autumn, or the removal of the
tree) it expands again, (called "heave"), putting more stress on the
weakened foundations. For that reason, if one suspects that a tree has
caused foundation movement, it's essential NOT to cut it down right
away. Depending on soil type and local climate, often such trees have to
be reduced slowly, over a year or two, but it's a judgement that needs
to be made by a qualified surveyor.

Don't try a DIY remedy on the tree until the problem has been properly
assessed by an expert.

Janet.

--
Isle of Arran Open Gardens weekend 21,22,23 July 2006
5 UKP three-day adult ticket (funds go to island charities) buys entry
to 26 private gardens

David wrote:
I don't know whether this is an appropriate question for this NG, but I
don't know where else to post it. If someone has a better recommendation,
I will be happy to take it there.

I have a suspicion that tree roots are stressing the foundation of my
house. However, the symptoms are not constant -- they vary with the time
of year.

My question: In general, do tree roots grow at different rates during
different seasons of the year?

Thank you very much for any thoughts.


Only unless you have a rather large tree right up against your walls,
something that no builder would allow.

Why do you think it's tree roots? Do you have cracks in the
foundation? Is part of the structure seperating? Is your home built
on a hill?

The natural rise and fall of the water table may play a role, otherwise
it could be the standard expanding and contracting of the structure
during the seasons and on very hot and cold days. (On hot days and
during the summer, the structure will expand and at night you will hear
creakings and odd noises that many people mistake for ghosts!!!! -Its
just the house settling back to normal. The opposite happens in the
winter, a house will "contract" during the cold winter night and might
make other weird sounds in the process.)

-Jason

Thank you all three, so much, for your worthy thoughts. I'll try to
respond to each.

First of all, I've already considered many things. But because of the
inconsistency of the symptoms, I have pretty much concluded that there is
more than one cause. What I am trying to do now is determine which of the
potential causes are real and which are not. That's how I got down to tree
roots -- which I admit was a pretty long shot. FWIW though, the trees in
question are Austrian Pines, probably 40' tall by now, and they are about
20' away from the house.

Thus far, the only cause in which I have high confidence is when the
neighbors irrigate too much for too long. (I mean mud and water appearing
in my own back yard.) But from all appearances they have stopped that
since I indicated to them the problems that it was causing. However, the
symptoms have only decreased, not stopped, which leads me to believe that
there is at least one additional (seasonal) cause.

George: The house is on a standard slab. Your point about clay expanding
and contracting is interesting. I had not thought of that. However, the
"soil" around here is really what they call "decomposed granite". I don't
think there is any clay in it at all. But I will follow up with the locals
to be sure.

Janet: As you see from the above, the trees are not deciduous; but I don't
know whether that is relevant. Re removing the trees, I really don't wish
to do that. But if only I could be sure that they were the next proximate
cause, (and not something worse), then I would just accept and live with
it.

Lucky: The primary symptoms are audible, however there are many hairline
cracks in the patio and garage floor. The rest of the house is carpeted so
its difficult to be sure what's under there. The house is not built on a
hill, but it is on the slope of some foothills. I have bored some 6' holes
around the house, to test for water, but so far none has appeared at the
bottom of any of them. (This was done after the neighbors stopped deep
watering.) So if it is a water table issue, it must be below that. I am
wondering if there might be a channel down there, which the bore holes
wouldn't locate unless they were right on the mark...(?)

Re thermal expansion and contraction, I have thought much on this already,
and recognize it well when it is happening; however the symptoms are so
inconsistent that I have almost eliminated this as a primary cause.

Thanks again, everyone, for your thoughts. I welcome any more...



On Wed, 14 Jun 2006 09:47:45 -0600, David wrote:

I don't know whether this is an appropriate question for this NG, but I
don't know where else to post it. If someone has a better recommendation,
I will be happy to take it there.

I have a suspicion that tree roots are stressing the foundation of my
house. However, the symptoms are not constant -- they vary with the time
of year.

My question: In general, do tree roots grow at different rates during
different seasons of the year?

Thank you very much for any thoughts.