Home Foundation Damage

[Cliff_Towle]

Customer advised by building engineer to remove two mature Ash & one mature Red Oak to mitigate foundation damage due to house settling. The engineer thinks the trees are drawing too much moisture away from the ground, thus causing the movement of the basement wall. The trees are 20ft away from the house. This is the first time in 20+ years I've heard of this. Any thoughts about it? Anyone else with similar experience? Thanks.

 

[evo]

Customer advised by building engineer to remove two mature Ash & one mature Red Oak to mitigate foundation damage due to house settling. The engineer thinks the trees are drawing too much moisture away from the ground, thus causing the movement of the basement wall. The trees are 20ft away from the house. This is the first time in 20+ years I've heard of this. Any thoughts about it? Anyone else with similar experience? Thanks.

Engineers tend to over think things in the organic world. I doubt it is causing settling. Seems like a finger pointing

 

[data farm 26]

Sounds like bullshit but I ain't no engineer

 

[southsoundtree]

What is seen on other sides of the house?

By 20', do you mean the butt is 20' away?

 

[Cliff_Towle]

What is seen on other sides of the house?

By 20', do you mean the butt is 20' away?

Yes, butt is 20 ft from house.

 

[Tom Dunlap]

Ask the engineer to spell photosynthesis before he pokes his nose into tree world

Then have him explain subsidence without using any reference material

His in/ability to pass both of these simple entry level tests will be key

Ask him for his ISA Certified Arborist number

Third strike

 

[flushcut]

Sounds like he engineered a poor foundation for the soil conditions. Is this a new house or existing?

 

[Basswood]

How did he come to this conclusion?

I recently went off on a building inspector for recommending trees be removed or topped to new prospective homeowners. It’s amazing what people think they know with absolutely zero investigation.

 

[Cliff_Towle]

Sounds like he engineered a poor foundation for the soil conditions. Is this a new house or existing?

existing.

 

[cerviarborist]

Assuming the building is on a slab, there's no moisture or oxygen in the soil beneath it for tree roots to exploit, so I'd take that engineers hypothesis with a bigass grain of salt.

Having said that, I once had a client who thought a tree might be causing their house to settle. Turns out the developer took all the removed vegetation from land clearing and buried it in a pit. At the end of the development, the pit was covered over with fill dirt, compacted and the last house built upon it. Years later, that biological matter had decayed enough to create a void and things began settling.

Ground Penetrating Radar might be useful in this instance, weighed against the cost of removing the trees and the loss of the benefits the trees are currently providing to the site.

 

[SeanRuel]

Maybe tell the engineer to try some fine aggregate compacting to improve soil stability near the foundation, or in layman's terms he can go pound sand

 

[Dan Cobb]

Assuming the building is on a slab,...

That would be a bad assumption since the OP said the problem was movement of a basement wall.

 

[ATH]

Forgetting for a moment that I value trees...

Lets look at this:
"The engineer thinks the trees are drawing too much moisture away from the ground, thus causing the movement of the basement wall"

No question about it that shrink/swell of soil causes damage to basement walls. I'm not in Kansas (anymore), but around here, it isn't the 'shrink' part of that equation that anybody worries about. It is the swelling that has pushing power.

Secondly, is the suggestion that if trees are gone, the soil against the foundation will not dry down as much? How strong of a certainty is that?

Third, how much MORE water will be added to the soil because they remove 3 giant water pumps (the trees...) from the system. This seems to have the potential to create more swell leading to more significant volume change when (not if) soil does dry down and shrink.

Finally, if the problem is things getting too dry, wouldn't a simple soaker hose on a timer solve that for hundreds of dollars (when you include the cost of the water) compared to thousands of dollars for tree removals.

Again...around here, the problem isn't vegetation. It is back-fill with clay rather than gravel and it is water not being diverted away from the foundation well.

 

[cerviarborist]

That would be a bad assumption since the OP said the problem was movement of a basement wall.

My bad. Florida boy here with not a lot of basement experience. I still think there's not enough evidence though to throw the trees under the bus.

 

[Bart_]

I was hoping to hear that the house was recently planted Agreed, moisture out, shrink, relieve contact pressure with foundation - engunearing you can't push a rope or pull a wall

 

[flushcut]

My bad. Florida boy here with not a lot of basement experience. I still think there's not enough evidence though to throw the trees under the bus.

At 20’ I have my doubts that the roots are a major issue. And his soil shrinkage theory is probably not the cause. Too much water in a freeze thaw cycle are the real destroyers of basement walls.

 

[cerviarborist]

According to a Seinfeld episode, shrinkage is a legit problem.

 

[flushcut]

Ah yes tis true, but the cold water was the root cause and shrinkage was the result.

 

[oldoakman]

Most of the engineers I deal with have tunnel vision. I seriously dou t he will change his mind.

My own experience with soil shrinkage and building settling is directly related to soil type and poor foundation planning. My home moves 1/2 to 3/4 inch throughout the year as the soil dries out or becomes wet.

 

[colb]

As silly as 20 feet seems, the appropriate person to comment on this root/house issue is both an engineer and an arborist.