Foundation Install with Interfering Surface Roots

[Hexa Fox]

Hey guys,

I have this ongoing project and I was hoping a knowledgeable arborist or at least someone knowledgeable with trees could advise me. I would really appreciate any feedback. So long story short, I have a large shed 12x16 on my property that is also pretty tall with a loft area. The problem with it is that it was installed and leveled on cinder blocks. Overtime the band boards on the building have started to splay out from under it and I need to get it addressed as soon as possible. Anyway, my plan is to just have a company move the building to another location on my property.

This has been stressing me out for awhile now because I need one company to lay the foundation and another to move it. Finally I have found a company to install a gravel pad as the foundation that has excellent reviews and they are going to compact it and add a wooden retaining wall around it. The problem that I am facing now is that there is a very large Silver Maple tree near where I wish the shed to go. I had a proposed location on my property marked off yesterday for where they will place the foundation. There are several surface roots from this tree in this area. The company said removing the surface roots would not be a problem and they do it all the time without problems. I know that removing surface roots can be problematic for trees though. The rep also said that this area would need to be dug out between about 4"-15" to make it level and make room for the gravel. So they are going to be going down a considerable amount on these surface roots and I have no clue how much more could be down there.

I also took a few pictures that I know may not do a whole lot but hoping it will help give you guys an idea of what I am dealing with. I also really do not want to remove the tree at this time but I sure do not want to kill it and it fall on top of the shed. That would be a disaster. There are definitely larger surface roots around this area but they are not directly inside of the location. I tried to bias the proposed location away from them. I also plan to try to have either 4x4's or 6x6's laid between the gravel bed and the shed frame and be able to anchor them somehow. Again I appreciate any feedback from you guys!

 

[Bullseye T&L]

There's a big difference between 4" and 15" when you're talking excavation and root removal. At 4" you might could get away with making a clean cut 4" down along perimeter then excavating. If you're going 15", then making a pruning line is going to be more difficult, and you may want to treat the tree with a growth regulator prior to excavation - which in human terms is like putting it to sleep before surgery. So a good soil sample first would help to know whether they need 4" or 15". They need solid ground to build up from, so I get the depth range.

I would take this up with them and see if they can give you a more exact depth prior to excavation. If not, then call a local arborist who does this kind of thing. Two points are 1) clean cut those roots along perimeter before excavating, and 2) don't excavate deep unless tree is in dormant state. I wouldn't try to bulldog a maple, at least down here in zone 7b/8a. Not sure what zone you're in.

 

[Hexa Fox]

There's a big difference between 4" and 15" when you're talking excavation and root removal. At 4" you might could get away with making a clean cut 4" down along perimeter then excavating. If you're going 15", then making a pruning line is going to be more difficult, and you may want to treat the tree with a growth regulator prior to excavation - which in human terms is like putting it to sleep before surgery. So a good soil sample first would help to know whether they need 4" or 15". They need solid ground to build up from, so I get the depth range.

I would take this up with them and see if they can give you a more exact depth prior to excavation. If not, then call a local arborist who does this kind of thing. Two points are 1) clean cut those roots along perimeter before excavating, and 2) don't excavate deep unless tree is in dormant state. I wouldn't try to bulldog a maple, at least down here in zone 7b/8a. Not sure what zone you're in.

Hey Bullseye,

Thanks for the advice. I was actually just reading another thread where you recommended something similar. So I want to make certain you understand, the reasoning for the difference in depth in my case is because of the grade. The rep said that the front right flag was the lowest and they would only need about 4" there but the back left flag was about 15" difference. So quite a bit. The roots are more toward the middle but on the left side. So they may be closer to 10" or something. I should have asked them to take a depth measurement there to see how much would need removed near the surface roots. I live in West Virginia so everything is on at least a slight incline lol. My zip code is 25414 if that helps you.

So you think I should try to find the roots or request the company find them right where they come into interference with the foundation and terminate them?