There is a 80-ft tall douglas fir tree three feet from my outside wall and
it has been there ever since the house was built some 20 years ago. I
recently read that roots of large tree could damage house foundation.
However, nobody else (including an arborist, a house inspector) who saw that
tree ever mentioned anything like that, although I didn't specifically ask
them about this issue.
On the other hand, my driveway was cracked by a much smaller tree (maple)
which forced me to cut it down. So "large tree roots may damage house
foundation" does have a ring of truth. On the third hand, if that was true,
the builder (and a reputable one) wouldn't have built the house 3 feet away
from that tree, would they?
Depends entirely on root type. Oaks have shallow roots systems, while
redwoods have deep tap roots. I had to take out 15 juniper bushes
because they craked my enitre sidewalk, but I've had 40' pines close to
the house that gave me no problems. Ask an arborist.
If I remember correctly, and I may not, a pine (fir) tree has roots that
resemble a carrot. Oaks, maples, etc have roots that spread out. The worst
of this type would be a weeping willow where the roots "hunt" for water.
But then, I may be totally wrong. I heard this a long time ago.
Arborists if not carefully chosen are just tree cutters, and may
overemphasize "dangers" of tree and roots in order to get a job.
House inspectors, the lowest of the low, often don't catch everything, and
there is no red flag here.
Even reputable builders often leave trees too close to houses in order to
make the house attractive and landscaped to sell. They tend to know little
about trees, but rather building and selling.
Dont sweat the foundation risk unless you see a hint of damage. If curious,
you can dig a test trench along your fdn to see size and orientation of
roots. Roots of practically all trees tend to look for moisture,and back off
from foundations, as under the house it is usually dry.
The biggest risk for your house is limbs falling on roof and invading
sewer/drainage lines, if they are the jointed metal or tile type. PVC with
glued joints tends to resist root damage.
BTW redwoods have no tap roots, as one poster suggested. Nearly all trees
have shallow roots. Here is a quote from the Dept. of Energy:
"Redwoods have the same kind of root system as any other tree. Usually,
the root systems of the redwoods stay close to the soil surface, only going
4-6 feet deep but spreading way beyond the tree, 250 feet in width. " Same
general principles apply to firs.
I have 60-85 foot Monterey Pines that have similar growth styles but smaller
than Douglas Firs, and they are within 18-25 feet of fdn. Perhaps three
feet is a bit close, but as said, I would just monitor fdn, and do test
trench to get root location/orientation. I have also used a bladed punch
bar to chop roots that are going the wrong way, or under driveways.. No real
harm to tree or its stability.
I stand corrected about redwood tree root systems. I was either
misinformed by my nursery when I planted redwoods on my property, or I just
didn't listen/remember. I just looked it up here:
Redwood trees have shallow, aggressive root systems that can raise havoc
with house foundations, sidewalks or lawn. Almost anytime improvements
compete with redwood tree roots, the roots will win.
Apologies for spreading non-factual information. I usually don't
contribute unless I sure of what I'm talking about, and this time I wasn't.
If it falls over and the roots are under the footings then you are totally
Otherwise, its a gamble--mosty dependant on the soil under the foundation,
Solid rock........(eeks !!!)
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.