Removing tree stumps or grind for under slab

[victor]

I am planning a garage that will be on a slab. I have several large tree stumps that I am considering grinding instead or digging out. What do ya think?

[Bill]

Termites love em. Might want ever else is close too...

[marson]

Ideally you would dig them out since obviously, where there is wood will someday be a void. However, you probably would be OK if you have rebar in the slab and the stump isn't under a footing.

[Craig M]

[PeterD]

Dig them out...

Consider this:

You will have to scrape off all the loam and topsoil anyway, often to

12 or more inches indepth, and lay down a bed of sand and/or gravel. That will leave a lot of roots exposed and make the grinding really more difficult.

In reality if the stumps were not near the edge, they'd probably not rot for many years, so that is not a problem, but the logistics of creating a good slab will make life difficult at best.

And, since you will have a backhoe and loader there to do the site prep, digging them out makes all the sense in the world. The only down side is that you then have to dispose of the stumps some way that is socially acceptable in your neck of the woods. It is not acceptable to bury them in most locations anymore (not that it is an environmental issue, it is not, but that so many contractors were lazy and didn't burry them deep enough and that resulted in nasty holes and other problems). As well, most landfills won't take stumps and often it is not allowed to burn them in an open fire.

But even so, dig them out, you will have a better slab, and it will be less work in the end.